Worksheet generator

1.C — 16KA-0050Working backwards

• AI added the 4 and the 6 and stopped, forgetting to undo the halving.
• BI doubled the 6 first and then added the 4, reversing the steps in the wrong order.
• DI doubled the total at the end rather than doubling only the amount left after the first spend.
• EI doubled twice because spending half felt like it needed undoing more than once.

2.C — 70KA-0055Place value and digit positions

• AI gave the last digit of the number instead of looking at the 7 at all.
• BI gave the digit itself rather than what it is worth in the position it sits in.
• DI counted the positions from the left, so I read the 7 as being in the hundreds place.
• EI gave the value of the largest digit instead of the value of the 7.

3.C — 210KA-0057Clever regrouping (pair to round numbers)

• AI paired the numbers from the outside in but left the 20 out of every pair, so I added only up to 19.
• BI estimated the total as a round number instead of working it out.
• DI used eleven pairs of 20 instead of ten pairs of 21.
• EI multiplied 20 by 21 and forgot that pairing counts every number twice.

4.C — 9KA-0072Systematic listing

• AI counted only the numbers with two identical digits, like 11, 22 and 33.
• BI required the two digits to be different, even though repeats are allowed.
• DI allowed a fourth digit that was not in the list.
• EI counted three-digit numbers instead of two-digit ones.

5.E — the two diagonals are the same lengthKA-0079Properties of triangles and quadrilaterals

• AI confused a rectangle with a square, which is only one special kind of rectangle.
• BI remembered a fact about squares and rhombuses and applied it to every rectangle.
• CI counted the two diagonals as lines of symmetry, which only works for a square.
• DI used the angle sum of a triangle on a four-sided shape.

6.B — 24KA-0083Perimeter and area of rectilinear shapes

• AI subtracted 6 from 20 and gave that, which is neither a side nor an area.
• CI took the other side to be 20 minus 6 divided by 2, forgetting there are two sides of each length.
• DI multiplied the perimeter by half the known side instead of finding the missing side first.
• EI used 16 as the other side, taking 20 minus 6 plus 2 rather than working from the perimeter properly.

7.A — blackKA-0108Repeating cycles and position mod n

• BI got a remainder of 1 but read the last colour of the repeat rather than the first.
• CI thought the pattern had no fixed first tile, even though tile one is given.
• DI assumed a repeating pattern must eventually change.
• EI assumed the pattern runs only for as many tiles as one repeat contains.

8.B — 280KA-0114Money and change

• AI subtracted the cost of one notebook rather than all three.
• CI bought two notebooks instead of three.
• DI gave the total cost of the notebooks instead of the change.
• EI converted the 10 euro note to 1000 cents but subtracted the price of only one notebook after doubling it.

9.B — 8KA-0119Find what is actually being asked

• AI halved the difference, as if the question asked how many Bo should hand over to make them equal.
• CI gave how many Bo has now rather than how many more he has than Ana.
• DI gave the number Bo started with, without doing anything.
• EI added the two amounts together instead of comparing them.

10.B — Write an answer for every one of themKA-0127Never leave a blank — there is no penalty

• AI treated guessing as dishonest, but the rules of the paper explicitly allow it and cost nothing.
• CI answered one and left two blanks that could each have scored, at no risk.
• DI tried to communicate with the marker, but only the answers are scored.
• EI offered working on a paper where only the chosen letter is marked.

11.D — 30KA-0007Working backwards

• AI added the 6 and the 9 and stopped, forgetting to undo the halving at the start.
• BI undid the steps in the order they were written instead of reversing the order as well as the operations.
• CI doubled the 9 first and then added the 6, which reverses the steps in the wrong order.
• EI doubled twice because giving half away felt like it should be undone more than once.

12.B — 2KA-0011Divisibility rules: 2, 3, 4, 5, 9, 10

• AI added the known digits to get 13 and then checked whether the missing digit itself was a multiple of 3.
• CI chose 3 because the question mentioned dividing by 3, without testing the digit sum at all.
• DI tested the last two digits, which is the rule for 4, not the rule for 3.
• EI added the digits but left out the 4 at the end, so my sum was four too small.

13.B — 2KA-0016Dice and cube face relationships

• AI used the upper die's touching face instead of the lower one, so I worked from 3 rather than 5.
• CI gave the number on a touching face itself rather than the number opposite it.
• DI subtracted 3 from 7 because I confused which die was sitting on which.
• EI gave the lower die's upward face, which is the number I was told, not the hidden one underneath.

14.C — 16KA-0019Multi-step arithmetic word problems

• AI found what one child has left and gave that instead of the total for all four.
• BI divided 24 by 4 and then subtracted 2 twice, mixing up per-child steps with total steps.
• DI subtracted 2 pencils once from the whole pack instead of once from each of the four children.
• EI subtracted the 2 before sharing, so only one lot of 2 ever came out of the total.

15.D — 9KA-0046Counting by position (sliding window)

• AI cut the board into four separate 2 by 2 blocks instead of sliding the square one step at a time.
• BI counted the three sliding positions along the top and doubled them for two rows.
• CI counted the positions along the top row and down the left column and added them.
• EI counted the sixteen small squares on the board rather than the 2 by 2 squares.

16.A — 3KA-0076Casework

• BI included 0 and 7 as a pair, even though both numbers have to be bigger than zero.
• CI counted both orders of each pair, even though swapping does not make a new way.
• DI counted every starting number from 1 to 7 without checking which pairs repeat.
• EI counted both orders and also allowed pairs of equal numbers.

17.D — 6KA-0085Line and rotational symmetry

• AI checked only the vertical and horizontal folds and stopped there.
• BI counted the lines through opposite corners and forgot the ones through opposite edges.
• CI assumed a hexagon behaves like a rectangle with a couple of extra folds.
• EI counted each line twice, once from each end.

18.B — 1KA-0089Building and counting with unit cubes

• AI assumed every small cube touches the outside somewhere.
• CI counted the cubes at the centre of each face, which are painted on one side.
• DI counted the corner cubes, which are the most painted rather than the least.
• EI gave the total number of small cubes instead of the unpainted ones.

19.B — 60KA-0093Weighing and balance puzzles

• AI halved the apple's weight, as if one apple balanced two pears.
• CI assumed a pear must weigh the same as an apple because the two sides balance.
• DI multiplied the apple's weight by three halves the wrong way round, making the pear heavier.
• EI gave the total weight of the two apples rather than the weight of one pear.

20.B — Bo onlyKA-0096Truth-tellers and liars

• AI took Ana's statement at face value without checking whether a truthful person could say it.
• CI decided nobody was lying without testing Ana's statement against that assumption.
• DI believed Ana's statement even after concluding she was a liar, which is what a liar's statement cannot be.
• EI gave up when Ana's statement looked circular, instead of testing one assumption all the way through.

21.B — Box X is not redKA-0099Reading a logical statement precisely

• AI read the rule backwards, as if being heavy were what makes a box red.
• CI assumed not red must mean one particular other colour, when the rule says nothing about which.
• DI contradicted the rule I was given rather than applying it to box X.
• EI decided one fact could not settle anything, without testing what would follow if X were red.

22.C — 25KA-0109Arithmetic sequences and the nth term

• AI added the step of 3 six times instead of seven, stopping at the seventh step.
• BI multiplied 3 by 8 without adding the first step's blocks.
• DI multiplied the step of 3 by 8 and added 4, taking one step too many.
• EI multiplied the first step's 4 blocks by the step number instead of following the pattern.

23.B — 21.5KA-0115Multi-step arithmetic word problems

• AI halved the 60 pencils before giving any away.
• CI subtracted 17 from one box of 12 rather than from the whole 60.
• DI gave the number of pencils left over rather than what each child gets.
• EI gave the starting number of pencils without doing either of the steps.

24.B — 7KA-0131Back-solve from the answer choices

• AI tested the first choice, got 13, and picked it anyway because it was close.
• CI added the 3 to 17 instead of subtracting it, then halved the 20 that gave me.
• DI subtracted 3 from 17 and gave that without halving it.
• EI added 3 to 17 instead of undoing the addition by subtracting it.

25.C — 8KA-0012Casework

• AI counted each pair of digits once instead of counting both orders, such as 17 and 71.
• BI listed the pairs starting from 1 and 7 and forgot the number 80, where the second digit is zero.
• DI included 08 as a two-digit number, but a two-digit number cannot start with zero.
• EI counted both orders of every pair and then counted the pairs that reverse to themselves twice as well.

26.B — 1KA-0017Truth-tellers and liars

• AI assumed everyone could be lying at once without checking that Cal's statement would then be true.
• CI found one consistent truth-teller and added another without testing whether both could hold together.
• DI assumed everyone was telling the truth without noticing that Ana's statement then contradicts Bo's.
• EI gave up after one assumption led to a contradiction, instead of trying the other assumption.

27.D — 8KA-0134Paper folding and hole punching

• AI forgot that the punch goes through every layer, not just the top one.
• BI undid only one of the two folds before counting.
• CI doubled twice for the folds but added the second hole instead of doubling for it too.
• EI counted three folds instead of two, doubling one time too many.

28.C — 25KA-0135Digit-constraint puzzles

• AI counted the odd numbers in one row of ten and treated that as the whole answer.
• BI used four odd digits instead of five, forgetting that 9 is odd.
• DI counted every two-digit number that is itself odd, which only fixes the last digit.
• EI let the first digit be any of ten values rather than only the five odd ones.

29.C — 14KA-0139Dice and cube face relationships

• AI subtracted only the top face from 21, forgetting the hidden bottom face as well.
• BI guessed four middling numbers and added them without using the total of all six faces.
• DI subtracted only the bottom face of 4 from the total of 21.
• EI added the four largest numbers on the die rather than the four that are actually at the sides.

30.C — 4KA-0140The multiplication principle

• AI counted the codes that do start with A rather than the ones that do not.
• BI counted the letters available for the first position instead of counting whole codes.
• DI counted every arrangement of the three letters and forgot the restriction.
• EI allowed letters to repeat, which the words each exactly once rule out.