Area of rectangles and squares | 3rd grade, 4th grade Math ... - Free Printable

Let’s solve each problem step by step.

We are finding the area of rectangles and squares.
To find area, we multiply:
length × width (or base × height — same thing!).

Units will be in square meters (m²), since all sides are given in meters.

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First row:

1. Rectangle: 21 m by 11 m
→ Area = 21 × 11
Let’s calculate:
20 × 11 = 220
1 × 11 = 11
Total = 220 + 11 = 231 m²

2. Square: 54 m by 54 m
→ Area = 54 × 54
We can do:
50 × 50 = 2500
50 × 4 = 200 → so 50 × 54 = 2700
Then 4 × 54 = 216
Wait — better way:
54 × 54 = (50 + 4) × (50 + 4) = 50² + 2×50×4 + 4² = 2500 + 400 + 16 = 2916 m²

Or just multiply:
54
× 54
------
216 ← 54 × 4
+2700 ← 54 × 50 (shifted left)
------
2916 → Yes!

3. Rectangle: 91 m by 78 m
→ Area = 91 × 78
Break it down:
90 × 78 = (9 × 78) × 10 = 702 × 10 = 7020
1 × 78 = 78
Total = 7020 + 78 = 7098 m²

Check with another method:
91 × 78 = (100 - 9) × 78 = 7800 - 702 = 7098 → Correct!

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Second row:

4. Rectangle: 63 m by 42 m
→ Area = 63 × 42
Break it:
60 × 42 = 2520
3 × 42 = 126
Total = 2520 + 126 = 2646 m²

5. Rectangle: 85 m by 69 m
→ Area = 85 × 69
Do: 85 × 70 = 5950, then subtract 85 → 5950 - 85 = 5865 m²

Check:
80 × 69 = 5520
5 × 69 = 345
Total = 5520 + 345 = 5865 → Correct!

6. Square: 22 mm? Wait — look again.

Actually, looking at the image description, the last one says “22 mm” but that must be a typo — because all others are in meters, and units should match. Also, in context, it's likely 22 m, not mm. Because if it were mm, area would be tiny and inconsistent.

Assuming it’s 22 m × 22 m (since it’s drawn as a square like others):

Area = 22 × 22 = 484 m²

(If it really were mm, we’d have to convert, but that doesn’t make sense here — probably a misprint.)

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Third row:

7. Square: 99 m × 99 m
→ Area = 99 × 99
= (100 - 1) × (100 - 1) = 10000 - 200 + 1 = 9801 m²

8. Rectangle: 55 m by 38 m
→ Area = 55 × 38
Do: 50 × 38 = 1900
5 × 38 = 190
Total = 1900 + 190 = 2090 m²

9. Rectangle: 89 m by 49 m
→ Area = 89 × 49
Do: 90 × 49 = 4410, then subtract 49 → 4410 - 49 = 4361 m²

Check:
80 × 49 = 3920
9 × 49 = 441
Total = 3920 + 441 = 4361 → Correct!

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Now let’s list all answers clearly:

1. 21 m × 11 m → 231 m²
2. 54 m × 54 m → 2916 m²
3. 91 m × 78 m → 7098 m²
4. 63 m × 42 m → 2646 m²
5. 85 m × 69 m → 5865 m²
6. 22 m × 22 m → 484 m² *(assuming typo from mm to m)*
7. 99 m × 99 m → 9801 m²
8. 55 m × 38 m → 2090 m²
9. 89 m × 49 m → 4361 m²

All calculations double-checked.

Final Answer:
231, 2916, 7098, 2646, 5865, 484, 9801, 2090, 4361