Area of a right triangle

Difficulty Starter · Set v9uo5b

The drawings are schematic: work from the lengths marked on them, not from their proportions.

Fill in what you can and press Check. Nothing you type is sent anywhere.

1
What is the area, in square cm?
2
What is the area, in square cm?
3
What is the area, in square cm?
4
What is the area, in square mm?
5
What is the area, in square mm?
6
What is the area, in square mm?
7
What is the area, in square mm?
8
What is the area, in square mm?
9
What is the area, in square cm?
10
What is the area, in square m?
11
What is the area, in square cm?
12
What is the area, in square mm?
13
What is the area, in square mm?
14
What is the area, in square m?
15
What is the area, in square m?
16
What is the area, in square mm?
17
What is the area, in square m?
18
What is the area, in square mm?
19
What is the area, in square cm?
20
What is the area, in square mm?

What is in this set

The numbers in this set run from 2 to 16.
A careful solution takes 2 written steps on average.
The mistake this set invites most often, in 100% of the problems: the base and the height were multiplied and left there; a triangle is half of the rectangle around it.
Answers are a whole number.

Drawing 240 problems from this page produced 122 different ones, 51% — so a sheet of 20 will come back to a problem you have seen — there are only so many sensible ones of this kind.

The same skill, harder or easier

We would put this in front of a grade 5 class. That is our judgement, not a standard, and it is printed here so you can disagree with it. Everything else we put in that year.