#### Answer

(a) To find the perimeter of an object whose sides are the same length, multiply that length by the number of sides.
(b) $3 \frac{3}{4}$

#### Work Step by Step

(a) Perimeter is the sum of the length of the sides of an object.
Repeated addition can be restated as multiplication. Adding a number to itself is the same as multiplying by 2. Adding the same number x times is the same as multiplying by x.
To find the perimeter of an object whose sides are the same length you can multiply that length by the number of sides.
(b) $\frac{15}{16} \times 4$ = $\frac{15}{16} \times \frac{4}{1}$
Use the common factor of 4 to reduce the fractions.
$\frac{15}{4} \times \frac{1}{1}$ = $\frac{15}{4}$
Restate as a mixed number.
$15 \div 4 = 3R3$ = $3 \frac{3}{4}$