Question

A sheet of cardboard is 1.6 m by 0.8 m. The following shapes are cut from the cardboard: ● a circular piece with radius 12 cm ● a rectangular piece 20 cm by 15 cm ● 2 triangular pieces with base 30 cm and height 10 cm. What is the area of the remaining piece of cardboard in m²? (Consider π = 22/7)

Answer 1

Answer:

1.17m²

Step-by-step explanation:

Total area of cardboard=

$1.6 \times 0.8 = 1.28m {}^{2}$

Area of circular piece=

$\pi \: r {}^{2} = ( \frac{22}{7} )(0.12) {}^{2} = \frac{198}{4375} m {}^{2}$

Area of rectangular piece=

$0.2 \times 0.15 = 0.03m {}^{2}$

Area of 2 triangular pieces=

$2( \frac{1}{2} \times 0.3 \times 0.1) = 0.03m {}^{2}$

Remaining area of the cardboard= Total area of cardboard - circular piece - 2 triangular pieces

$1.28 - \frac{198}{4375} - 0.03 -0.03 = \frac{21083}{17500} =1.17m {}^{2}$