Learn by Novus · Open practice pack v1

Working memory: hold, update, and manipulate: open practice pack: worked explanations

100 untimed questions across 10 authored sections.

This is untimed educational practice for one cognitive skill. It is not a clinical, diagnostic, employment, or professionally recognized assessment, and it does not produce an IQ score or credential.

Worked explanations

working-memory-s01-q01

First digit 8 + last digit 9 = 17.

working-memory-s01-q02

With 5 letters, the middle (3rd) position holds P.

working-memory-s01-q03

Basket and Candle each have 6 letters; Umbrella has 8.

working-memory-s01-q04

Reading backward: 1 (1st), 5 (2nd), 9 (3rd).

working-memory-s01-q05

apple (3) + cherry (2) = 5.

working-memory-s01-q06

Circle appears twice: 1st and 3rd positions.

working-memory-s01-q07

Add as you go rather than at the end: 5 + 2 = 7, then 7 + 8 = 15. Keeping a running total lightens the memory load.

working-memory-s01-q08

Rehearsing the list once in order (lamp, river, stone) fixes the positions: River sat in the second slot.

working-memory-s01-q09

Replaying the sequence in order (T, F, B, X) shows B follows straight after F.

working-memory-s01-q10

Tally each colour as it passes: green appears in the 2nd and 4th positions, so twice.

working-memory-s02-q01

The sequence was 7, 1, 8, 4, counting along it puts 8 in the third position. Grouping digits into pairs (71, 84) makes short sequences easier to hold.

working-memory-s02-q02

The list ended with BRICK. The last item in a studied list is often the freshest in memory, a pattern called the recency effect.

working-memory-s02-q03

The order was G, M, S, K, V, so the third letter was S. Middle items are the hardest to recall, which makes them worth an extra rehearsal while studying.

working-memory-s02-q04

The studied list was spoon, ladder, candle, marble, ribbon, carpet never appeared. Checking each option against your mental list one at a time avoids false recognition.

working-memory-s02-q05

The sequence 3, 9, 9, 2, 6 repeats only the 9, in the second and third positions. Noticing a repeat while studying gives you a strong anchor for later recall.

working-memory-s02-q06

The order was Priya, Callum, Nadia, Tomas. Callum came directly before Nadia. Replaying the list as a spoken rhythm helps preserve neighbouring pairs.

working-memory-s02-q07

The instruction specified the second door on the right. Turning directions into a quick mental walk-through makes them far easier to retain than the words alone.

working-memory-s02-q08

The sequence mixed Q, R, and Z with the digits 4 and 7, three letters in total. Sorting items into categories while studying is itself a working-memory exercise.

working-memory-s02-q09

Counting along violet, amber, teal, coral, olive, slate places olive fifth. With six items, chunking into two groups of three keeps the positions straight.

working-memory-s02-q10

The sequence ended ... 1, 9, 3, so the second-to-last number was 9. Seven digits sits near the limit of most people's span: chunking (62, 75, 193) helps.

working-memory-s03-q01

Reversing 4 - 1 - 7 gives 7 - 1 - 4. A useful shortcut: reversing any sequence leaves the middle element exactly where it was, so it is still 1.

working-memory-s03-q02

The first letter of a reversed sequence is simply the last letter of the original. Here that is A, with no need to reverse the whole thing.

working-memory-s03-q03

Reading 2 - 8 - 5 - 3 from the end gives 3, 5, 8, 2, so the first two digits backwards are 3 then 5. Working from the tail end is easier if you rehearse the sequence once forwards first.

working-memory-s03-q04

Reversed, the sequence reads 7, 2, 6, 4, 9, putting 4 in the fourth position. Equivalently, the fourth-from-the-front of the reversed list is the fourth-from-the-back of the original.

working-memory-s03-q05

The studied sequence 5, 8, 1, 6 reversed is 6, 1, 8, 5. Doing this from memory combines storage and manipulation: the core of working memory.

working-memory-s03-q06

Swapping the ends of L - D - Q - J - X moves X to the front and L to the back, so the sequence now starts with X.

working-memory-s03-q07

Sorted, the digits run 2, 3, 7, 9. The third is 7. Re-sorting held material is harder than reversing because every element changes position.

working-memory-s03-q08

Moving the 6 to the end gives 1, 8, 4, 5, 6, whose middle (third) digit is 4. Visualising the digits sliding one place left makes the shift concrete.

working-memory-s03-q09

Reversing the order gives OAK, MINT, PEAR, so the middle word is still MINT, and spelt backwards it reads TNIM. Handling two transformations in a row is a genuine two-step hold.

working-memory-s03-q10

The reversed sequence starts 4, 6, and 4 + 6 = 10. Notice you only ever needed the last two digits of the original, spotting shortcuts reduces the load.

working-memory-s04-q01

Update after every step: 5 + 3 = 8, 8 − 2 = 6, 6 + 4 = 10. Discard each old value as you go, only the current total needs holding.

working-memory-s04-q02

Apple has a and e (2), kiwi has i and i (2), plum has u (1). A running tally reaches 5.

working-memory-s04-q03

Track the floor after each move: 3 up to 7, down to 5, up to 6. Picturing the lift moving makes each update easier to hold than raw arithmetic.

working-memory-s04-q04

Only the first letter changes: C becomes P while A-R-T stay put, giving PART. Editing one element of a held word is a small but genuine act of updating.

working-memory-s04-q05

The evens are 4, 2, 6, and 8, a tally that ticks up to 4. Saying the count in your head at each hit stops it slipping while you scan the next number.

working-memory-s04-q06

Step by step: 20 halved is 10, plus 6 is 16, minus 9 is 7.

working-memory-s04-q07

LEFT appears four times and RIGHT twice, so A finishes on 4 and B on 2. Running two counters at once is what makes this harder than a single tally.

working-memory-s04-q08

Count down in steps: 50 to 43, to 36, to 29. Alternatively, 3 × 7 = 21 subtracted in one go gives the same 29, but the step-by-step version is the memory workout.

working-memory-s04-q09

Follow each hop: B forward two is D, back one is C, forward three is F. Saying each intermediate letter aloud in your head keeps the chain intact.

working-memory-s04-q10

Update the stock after every movement: 12 − 5 = 7, 7 + 8 = 15, 15 − 6 = 9, 9 + 2 = 11. Four updates in a row is where unrehearsed totals start to slip.

working-memory-s05-q01

Doubling 6 gives 12, and DOG has 3 letters, so 12 + 3 = 15. The trick is holding the intermediate 12 while you count the letters.

working-memory-s05-q02

TRAIN loses its T to become RAIN, then gains an S at the end to become RAINS. Applying edits one at a time, in order, prevents the steps blurring together.

working-memory-s05-q03

9 is odd, so add 5 to reach 14; 14 is even, so halve it to reach 7. Check each condition against the current value, not the starting one.

working-memory-s05-q04

North, right turn to east, right again to south, then a left turn from south faces you east. Imagining yourself physically rotating keeps each turn anchored.

working-memory-s05-q05

TABLE, DESK, and SHELF each contain an E; CHAIR and LAMP do not, so the count is 3. Holding the rule steady while scanning is the real work here.

working-memory-s05-q06

47 reversed is 74, and 74 + 2 = 76. A common slip is adding 2 before reversing. The order of steps matters.

working-memory-s05-q07

M moves forward to N. N does not come after P, so the otherwise-branch applies: one more forward lands on O. Conditional steps demand you test before you move.

working-memory-s05-q08

Swapping the S and T of STONE gives TSONE, with the remaining letters O-N-E untouched. Focus the swap on exactly the two named positions.

working-memory-s05-q09

14 is over 10, even, and not divisible by 6, so it passes all three tests. 12 and 18 fail the multiple-of-6 condition, and 9 is odd, checking every candidate against every held condition is the exercise.

working-memory-s05-q10

3 × 4 = 12, then 12 − 5 = 7, then 7 × 7 = 49. The final squaring only works if the 7 was held accurately through the earlier steps.

working-memory-s06-q01

The studied word was HARBOUR. Doing arithmetic in between creates interference: attaching a quick image (boats in a harbour) protects the word against it.

working-memory-s06-q02

The studied number was 58. Counting backwards floods the same verbal rehearsal loop the number lives in, which is exactly why distractor tasks make digits slip.

working-memory-s06-q03

The studied pair was CANDLE and ORANGE. The near-miss alternatives share sounds or meanings with the originals. Precise recall beats gist here.

working-memory-s06-q04

The sequence was 4, 9, 1, so the middle number was 9. Note how easily the 17 from the distractor task tries to intrude on recall, recognising intrusions is part of the skill.

working-memory-s06-q05

Of the held letters, T comes later in the alphabet than K. The counting task in between forces you to protect the letters while attention is elsewhere.

working-memory-s06-q06

The studied note was 3 lemons. Binding the number to the item as a single picture, three lemons in a row, keeps quantity and object from drifting apart.

working-memory-s06-q07

The studied order was 7, 2, 5. Order errors, recalling the right digits in the wrong sequence, are the most common failure once a distractor intervenes.

working-memory-s06-q08

The studied phrase was GREEN DOOR. Visualising an actual green door makes the pairing far more robust than rehearsing the two words separately.

working-memory-s06-q09

34 + 81 = 115. This item stacks interference and computation: the studied numbers must survive the multiplication before you can even start adding them.

working-memory-s06-q10

The studied allocation was Row F, Seat 12. The wrong options transpose or nudge one detail each. Exactly the errors interference tends to produce with letter-number pairs.

working-memory-s07-q01

One tea (£2) plus two scones (2 × £3 = £6) totals £8. The juice price is a deliberate extra load. Part of the skill is holding values you end up not needing.

working-memory-s07-q02

Substitute first, then compute: (5 × 2) + 8 = 10 + 8 = 18. Translating each symbol before starting the arithmetic keeps the two jobs from colliding.

working-memory-s07-q03

Red (4 kg) plus green (5 kg) makes exactly 9 kg; the other pairs give 11 kg and 12 kg. Testing pairs systematically stops you re-checking combinations you have already ruled out.

working-memory-s07-q04

From the studied values, 6 + 9 − 1 = 14. The recall and the arithmetic are separate steps: retrieve all three numbers first, then compute.

working-memory-s07-q05

Doubling each of 5, 3, 8 in turn gives 10, 6, 16. The challenge is keeping the already-transformed digits fixed while you work on the next one.

working-memory-s07-q06

The distances from 11 are: Anna 1, Ben 2, Chloe 4, so Anna is closest. Converting each held score into a distance is the manipulation step.

working-memory-s07-q07

Mentally re-ordering the times gives 09:20, 09:35, 09:45. The tram's 09:35 departure is second. The list arrives unsorted on purpose.

working-memory-s07-q08

The 22 tins split equally as 11 each, so shelf A must pass 3 of its 14 across. Equivalently, move half the difference: (14 − 8) ÷ 2 = 3.

working-memory-s07-q09

6 × 4 = 24, and the held 27 exceeds it by 3. The held number must survive the multiplication intact before the comparison can happen.

working-memory-s07-q10

Chain the conversions: 2 tokens = 6 stars, and 6 stars = 12 coins. Two-step unit chains require holding the middle quantity just long enough to convert it again.

working-memory-s08-q01

Substituting gives 4 + 7 + 4 = 15. Reading the symbols as their numbers in one smooth pass is quicker than translating each one separately.

working-memory-s08-q02

ALARM contains two As, in the first and third positions, and replacing both gives OLORM. Scanning for every occurrence, not just the first, is the point of the rule.

working-memory-s08-q03

Applying the mapping digit by digit, 3 becomes F, 1 becomes D, and 2 becomes B, so the decoded sequence is F, D, B, keeping the original order.

working-memory-s08-q04

Each letter moves forward once: B becomes C and each E becomes F, giving CFF. Apply the shift uniformly: every letter, exactly one place.

working-memory-s08-q05

Follow the symbols in order: 6 + 10 = 16, 16 − 4 = 12, 12 + 10 = 22. You are holding both the code and a running total at once. A genuine dual load.

working-memory-s08-q06

One application turns cat into dog; applying the mapping again turns dog into bird. Chained substitutions require re-consulting the held rule at every step.

working-memory-s08-q07

C is 3, A is 1, and B is 2, so CAB totals 3 + 1 + 2 = 6. Decoding and summing in a single left-to-right pass keeps the load manageable.

working-memory-s08-q08

2 is even (E), 5 is odd (O), and 8 is even (E), so the sequence becomes E, O, E. Judging each number afresh against the rule avoids drifting into alternation on autopilot.

working-memory-s08-q09

The chain runs 4 doubled to 8, plus 3 to 11, doubled again to 22. Keeping two named rules and a running value alive together is the heart of rule-based working memory.

working-memory-s08-q10

Stepping each coded letter back one place turns H into G, B into A, U into T, and F into E, spelling GATE. Decoding letter by letter while holding the partial answer is the exercise.

working-memory-s09-q01

Jar B receives 2 marbles, then 1 more from jar A, finishing on 3. A transfer changes both jars at once: update the two totals together.

working-memory-s09-q02

After Beth passes Amir the order is Beth, Amir, Cara; when Cara then passes Amir it becomes Beth, Cara, Amir. Re-stating the full order after every overtake prevents position slips.

working-memory-s09-q03

Home scores 2 + 1 = 3 goals and Away scores 1 + 2 = 3, so the match ends level at three each. Keeping two independent tallies is the load here.

working-memory-s09-q04

The kettle becomes 5 + 3 = 8 and the toaster becomes 2 × 2 = 4. Each value gets a different operation, so pairing the right rule with the right item is half the task.

working-memory-s09-q05

The first swap gives blue, red, green; the second swaps the middle and right cups to give blue, green, red. Visualising actual cups sliding makes each swap easier to hold than the colour names alone.

working-memory-s09-q06

SALT, STAR, and SOFT start with S (three words); SALT, NET, and SOFT end with T (three words). Note that SALT and SOFT legitimately count towards both tallies.

working-memory-s09-q07

After the first stop the cart holds 10 − 4 + 2 = 8 books; halving at the second stop leaves 4. The halving must apply to the updated total, not the starting one.

working-memory-s09-q08

Three steps in total move C3 to D4, then E5, then F6. Letter and number must advance in lockstep: updating one and forgetting the other is the classic error.

working-memory-s09-q09

Switch 1 is flipped twice, returning it to off, while switches 2 and 3 are each flipped once and stay on. An even number of flips always cancels out.

working-memory-s09-q10

The transfer leaves P with £30 and lifts Q to £35; Q's £15 payment then drops it to £20, so P holds more with £30. The transfer touches both balances: the payment only one.

working-memory-s10-q01

From the studied rules: 9 doubled is 18, minus 4 is 14, doubled again is 28. Everything (start value, both rules, and their order) had to be recalled before computing.

working-memory-s10-q02

Swapping the middle two gives 2, 3, 5, 6, and the first plus third of that new order is 2 + 5 = 7. The reordering must fully settle before the addition starts.

working-memory-s10-q03

316 reversed is 613, and the smallest digit of the original (1) brings it to 612. Both the reversed number and a fact about the original must be held simultaneously.

working-memory-s10-q04

PLANET without its last letter is PLANE, which reversed reads ENALP, and its second letter is N. Each transformation output becomes the next step's input.

working-memory-s10-q05

Monday's 4 plus Wednesday's 5 makes exactly 9; the other pairings give 8, 11, and 6. Four recalled values must all stay available while you test combinations.

working-memory-s10-q06

8 is even so it becomes 13; 13 is odd so it doubles to 26; 26 exceeds 20 so it drops to 25. Each condition tests the current value, so the chain must be walked strictly in order.

working-memory-s10-q07

Taking each digit from 10 gives 10 − 9 = 1, 10 − 2 = 8, 10 − 6 = 4, and 10 − 4 = 6, so the sequence becomes 1, 8, 4, 6. Transformed digits must not contaminate the ones still waiting.

working-memory-s10-q08

After the first swap the seats hold Kofi, Ben, Aisha, Lena; the second swap exchanges Ben and Lena, leaving Lena in seat 2. Re-listing all four seats after each swap keeps the state accurate.

working-memory-s10-q09

7 days × 3 = 21 and 4 sides × 2 = 8, so 21 − 8 = 13. Retrieving the everyday facts, computing both parts, and holding the first result through the second is the full layered load.

working-memory-s10-q10

The tokens total 2 + 5 + 7 = 14; halved that is 7, and adding the red token's value of 2 gives 9. The colour mapping must survive right to the final step, because red is needed again at the end.