Question

1. a circle has radius 6 cm. find its circumference (use π = 3.14). 8. a square has side length 20 m. find its perimeter. 9. a square has side length 20 m. find its area. 10. a rectangle is 25 ft long and 10 ft wide. find its area. 11. a rectangle is 25 ft long and 10 ft wide. find its perimeter.

Explanation:

Step1: Recall circle - circumference formula

The formula for the circumference of a circle is $C = 2\pi r$.

Step2: Substitute values

Given $r = 6$ cm and $\pi=3.14$, we have $C=2\times3.14\times6$.

Step3: Calculate

$C = 37.68$ cm.

Step4: Recall square - perimeter formula

The perimeter of a square is $P = 4s$, where $s$ is the side - length. Given $s = 20$ m, then $P=4\times20$.

Step5: Calculate

$P = 80$ m.

Step6: Recall square - area formula

The area of a square is $A=s^{2}$. Given $s = 20$ m, then $A = 20^{2}$.

Step7: Calculate

$A=400$ m².

Step8: Recall rectangle - area formula

The area of a rectangle is $A = lw$, where $l$ is the length and $w$ is the width. Given $l = 25$ ft and $w = 10$ ft, then $A=25\times10$.

Step9: Calculate

$A = 250$ ft².

Step10: Recall rectangle - perimeter formula

The perimeter of a rectangle is $P=2(l + w)$. Given $l = 25$ ft and $w = 10$ ft, then $P=2(25 + 10)$.

Step11: Calculate

$P=2\times35=70$ ft.

Answer:

1. $37.68$ cm
2. $80$ m
3. $400$ m²
4. $250$ ft²
5. $70$ ft