Skip to main content

Atlas
Problems
Diagnostic
Mock
Papers
About

The whole Atlas

Number & Arithmetic15
Counting18
Geometry & Visualization18
Logic & Deduction11
Patterns & Sequences7
Modeling & Word Problems10
Contest Craft12

Loading…

About
Sign in
Worksheets
Privacy
Terms
License
Contact
GitHub

Code is MIT. Problems, skills, and explanations are CC BY-NC-SA 4.0. Practice never requires an account and nothing here is paywalled.

Independent project. Not affiliated with or endorsed by Math Kangaroo in USA, NFP.

Home
Atlas
Problems
Papers

Browse the problems

177 problems, every one written from scratch, every wrong answer carrying the mistake that produces it. 708 explanations in all.

Level

1–2
3–4
5–6
7–8
9–10
11–12

Point value

3 pt
4 pt
5 pt

Strand

NUMNumber & Arithmetic
CNTCounting
GEOGeometry & Visualization
LOGLogic & Deduction
PATPatterns & Sequences
MODModeling & Word Problems
CFTContest Craft

Sort

Id
Hardest first
Newest

36 problemsClear all filters

KA-0065
4 points, difficulty 2 of 3Level 5–6not yet calibrated
A price goes up by 20%, then down by 20%. Compared with the original price, the final price is:
NUM-10Percentages and simple discountsalso NUM-09
KA-0066
4 points, difficulty 2 of 3Level 5–6not yet calibrated
The mean of four numbers is 9. Three of them are 5, 8 and 12. What is the fourth?
NUM-15Means, and working backwards from a meanalso LOG-08
KA-0069
4 points, difficulty 2 of 3Level 5–6not yet calibrated
In a class of 30, 18 play football and 14 play chess. 6 play both. How many play neither?
CNT-10Inclusion–exclusion with two setsalso CNT-09
KA-0073
4 points, difficulty 2 of 3Level 5–6not yet calibrated
How many different four-letter arrangements can be made from the letters of the word MATH, using each letter once?
CNT-05Arrangements of a few objectsalso CNT-03
KA-0074
4 points, difficulty 2 of 3Level 5–6not yet calibrated
Two students are chosen from a group of six to represent the class. How many different pairs are possible?
CNT-06Selections of a few objectsalso CNT-08
KA-0080
4 points, difficulty 2 of 3Level 5–6not yet calibrated
An isosceles triangle has an angle of 100 degrees. How big is each of the other two angles?
GEO-06Properties of triangles and quadrilateralsalso GEO-05
KA-0084
4 points, difficulty 2 of 3Level 5–6not yet calibrated
A square of side 6 cm is cut along a midline into two identical rectangles. What is the perimeter of one of them?
GEO-03Area by dissection and rearrangementalso GEO-01
KA-0087
4 points, difficulty 2 of 3Level 5–6not yet calibrated
Two similar triangles have areas of 9 and 25 square units. A side of the smaller one is 6 units. How long is the matching side of the larger one?
GEO-16Scaling and similar figuresalso NUM-11
KA-0092
4 points, difficulty 2 of 3Level 5–6not yet calibrated
Five children queue up. Ana is somewhere ahead of Bo. Cal is behind Bo but ahead of Dee. Eve is last. Who is second in the queue?
LOG-04Ordering and ranking from cluesalso LOG-01, CFT-02
KA-0100
4 points, difficulty 2 of 3Level 5–6not yet calibrated
A number is doubled, then 6 is added, then the result is halved. The answer is 11. What was the original number?
LOG-08Working backwardsalso MOD-01
KA-0103
4 points, difficulty 2 of 3Level 5–6not yet calibrated
A sequence starts at 3. Each term after that is double the one before it, minus 1. What is the sixth term?
PAT-05Recursive rulesalso PAT-02
KA-0104
4 points, difficulty 2 of 3Level 5–6not yet calibrated
A sequence starts 1, 1, and every term after that is the sum of the two before it. What is the eighth term?
PAT-05Recursive rulesalso PAT-04

1
2
3

Showing 13–24 of 36

Browse the problems — Kangaroo Atlas