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The length of a rectangle is 14.8cm. If you increase its length by 6.5cm and keep its width unchanged, the area will increase by 67.6cm2. What is the original area of this rectangle?
14.8x(67.6÷6.5)
=14.8x10.4
=153.92cm²
A: the area of a rectangle is 153.92 cm
A rectangle is 12cm long and 5cm wide. Enlarge it by 4:1. The area of the enlarged rectangle is ()
Both length and width are magnified 4 times
Then the area will be enlarged by 4 * 4 = 16 times
So the area is 12 * 5 * 16 = 960cm ^ 2
If the length of a rectangle is reduced by 5 cm, the area will be reduced by 20 square cm. If the width is increased by 3 cm, the area will be increased by 30 cm. What is the area of the original rectangle?
20 △ 5 = 4cm, find out the original width
30 △ 3 = 10 cm, find out the original length
10 × 4 = 40 square centimeter, calculate the area of the original rectangle
If the length of a rectangle is increased by 5cm and the area is increased by 30cm, the width of the original rectangle is () cm. If the length of the original rectangle is 20cm, the area is () cm
Please write the formula,
If the length of a rectangle is increased by 5cm and the area is increased by 30cm, the width of the original rectangle is (6) cm. If the length of the original rectangle is 20cm, its area is 120cm
30 △ 5 = 6cm
Area = 20 × 6 = 120 square centimeter
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