Question

From a metal sheet in the shape of trapezium with parallel sides $64\text{cm}$ and $100\text{cm}$ and height $56\text{cm},$ a circle of radius $7\text{cm}$ are cut out. Find the area of the metal sheet that it left.

• A. $230{\text{cm}}^2$
• B. $260{\text{cm}}^2$
• C. $4438{\text{cm}}^2$
• D. $250{\text{cm}}^2$

Answer 1

The correct option is C $4438{\text{cm}}^2$

Area of sheet left $=$ Area of trapezium - Area of circle

$=$ $\frac{1}{2}\times \text{sum of parallel sides}\times \text{height}-\pi r^2$

$=$ $(\frac{1}{2}\times (64+100)\times 56-\frac{22}{7}\times 7\times 7){\text{cm}}^2$

$=$ $(4592-154){\text{cm}}^2$

$=$ $4438$ ${\text{cm}}^2$