Pick what you want, print the page. The answer key comes with it, on its own sheet, and it tells you the mistake behind every wrong choice — not just which letter is right.
This exact URL always produces this exact sheet — bookmark it and the answer key will still match next term. Print with your browser; the controls and the site navigation are left off the page.
1.Bo has 24 marbles and gives a third of them to Ana. How many more marbles does Bo have than Ana now?[3]
A4
B8
C16
D24
E32
2.A cat walks 3 m north, then 4 m east, then 3 m south. How many metres is it now from where it started?[3]
A0
B3
C4
D7
E10
3.Which of these is closest to the number of seconds in one day?[3]
A1440
B3600
C24000
D60000
E86400
4.One minute is left. Three questions have no answer written and you cannot do any of them. Nothing is taken off for a wrong answer. What should you do?[3]
ALeave them blank, because guessing is not really doing the maths
BWrite an answer for every one of them
CAnswer only the one you nearly understand
DLeave them blank so it is clear you ran out of time
EWrite your working instead of an answer
5.Which of these numbers has exactly 6 different whole-number factors, counting 1 and the number itself?[4]
A12
B15
C16
D25
E27
6.A rectangle has an area of 36 and sides that are whole numbers. Which of these could NOT be its perimeter?[4]
A24
B26
C28
D30
E40
7.Twice a number, with 3 added, gives 17. Which of the choices is the number?[4]
A5
B7
C10
D14
E20
8.Ana has exactly 5 coins, each worth either 2 cents or 5 cents. Which of these could NOT be her total?[4]
A13
B16
C19
D21
E25
9.A diagonal joins two corners of a shape that are not next to each other. How many diagonals does a hexagon have?[4]
A6
B9
C12
D15
E18
10.You are 20 minutes into a 75-minute paper of 30 questions, still on question 9, and four minutes in with no progress. What is the best move?[5]
AKeep going — four minutes are already invested
BAnswer it with your best guess, mark it, and move on
CSkip it, leave it blank, and come back at the end
DGo back and re-check questions 1 to 8
EJump to question 30 and work backwards
Kangaroo Atlas · https://kangaroo-atlas.vercel.app · seed 1 · CC BY-NC-SA 4.0 · Independent project, not affiliated with Math Kangaroo in USA, NFP.
Answer key — Math Kangaroo practice
Each wrong choice carries the thinking that produces it. When a student picks C, this is what they were doing.
1.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.
2.C — 4KA-0120Draw the diagram
AI assumed the walk was a loop because the north and south distances match.
BI gave one of the distances walked rather than the distance from the start.
DI added the two different directions together instead of drawing where the cat ends up.
EI added up the whole distance walked, which is not the same as the distance from the start.
3.E — 86400KA-0124Estimate to the nearest choice
AI gave the number of minutes in a day instead of the number of seconds.
BI gave the number of seconds in one hour rather than in a whole day.
CI multiplied the 24 hours by a round thousand instead of converting properly.
DI multiplied 60 by a round thousand, using one conversion and inventing the other.
4.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.
5.A — 12KA-0122Back-solve from the answer choices
BI assumed a number with two different prime factors always has six factors.
CI counted the factors of 16 as six by including a number twice.
DI assumed a square number has six factors without listing them.
EI counted the powers of 3 up to 27 and thought there were six of them.
6.C — 28KA-0123Eliminate impossible choices by bounding
AI ruled out the square 6 by 6, forgetting that a square is a rectangle.
BI did not think to try 4 by 9, so I judged this perimeter impossible.
DI missed the 3 by 12 rectangle when listing the factor pairs.
EI stopped listing factor pairs before reaching 2 by 18.
7.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.
8.D — 21KA-0132Eliminate impossible choices by bounding
AI did not try one five and four twos, so I judged this total impossible.
BI missed the combination of two fives and three twos.
CI stopped listing after two fives and never reached three fives and two twos.
EI forgot the case where every coin is a five, which is allowed by the wording.
9.B — 9KA-0150Try small cases first
AI counted one diagonal from each corner and stopped there.
CI counted three diagonals from each corner but forgot that each one gets counted from both ends.
DI counted every line joining two corners, including the six sides.
EI multiplied six corners by three diagonals each and never halved.
10.B — Answer it with your best guess, mark it, and move onKA-0126Time triage: now, later, or guess
AI let the time already spent decide, but that time is gone whatever I do next.
CI moved on but left a blank, which scores nothing if I never get back to it.
DI spent time re-reading work I had no reason to doubt, while 21 unseen questions waited.
EI assumed the hardest questions are the best use of time, when the unseen easy ones are worth the same each.