If the diagonal of a square is double, how does the area of the square change?

The area of a circle of radius 5 is numerically what percent its circumference?

A rectangle has 20 cm as its length and 200 sq cm as its area. If the area is increased by 1 1/ 5 time the original area by increase its length only then the perimeter of the rectangle so formed (in cm) is

If the area of a semi-circle be 77 sq m, find its perimeter.

If the circumference of a circle is increased by 50%, then its area will be increased by?

If the area of an equilateral triangle is x and its perimeter is y, then which one of the following is correct?

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