Question

# The base of a prism is a right angled triangle with dimensions as follows: base =15 cm and altitude= 8 cm. If the height of the prism is 20 cm, the total surface area of the prism will be equal to: 860 cm2 820 cm2 920 cm2 960 cm2

Solution

## The correct option is C 920 cm2 Base of the prism is a right angled triangle having base and altitude as 15 cm and 8 cm respectively. Third side of the triangle will be equal to √(15)2+(8)2=√225+64=√289=17 cm Total surface area = Lateral surface area +  2× Base Area Lateral Surface Area =BasePerimeter× Height = 20(15+8+17) cm2 =20(15+8+17)+2×12×15×8 =20(15+8+17)+15×8 =20×40+120 =800+120 =920 cm2 Hence the Total Surface Area =920 cm2

Suggest corrections