Question

The sides of a triangle are in the ratio 3:4:5. If the shortest side measures 9 cm, what is the perimeter of the triangle ?

• A. 26 cm
• B. 21 cm
• C. 36 cm
• D. 16 cm

Answer 1

The correct option is C

36 cm

Let the sides of the triangle be 3$x$ , 4$x$ and 5$x$

Given that shortest side is 9 cm

Hence 3$x$ = 9

$x$ = 3

$\therefore$ the other two sides are 3(4) = 12 cm and 3(5) = 15 cm

Perimeter is the sum of all the sides .

Hence perimeter of the triangle = 9 + 12 + 15 = 36 cm