Question

Find the area of shaded region if radius of outer circle is 14cm and radius of inner circle 7 cm.​

Answer 1

$\huge{\mathfrak{\dag{\underline{\red{A{\green{n{\orange{s{\blue{w{\pink{e{\purple{r}}}}}}}}}}}}}}}$

Area of shaded region = Area of outer circle - Area of inner circle

= πR² - πr²

= π(R² - r²)

= π(14² - 7²)

= π[(14+7)(14-7)] {using a²-b² identity}

= π[(21)(7)]

= π x 147

$= \frac{22}{7} \times 147$

$= 22 \times 21$

$= 462$