Question

The cost of painting the circle is ₹30 per sq. ft. Calculate the total price of painting the circle of given diameter 9 ft. (round off to 2 decimal places)
$\text{[Take 𝛑=}\frac{22}{7}]$

• A. ₹2545.8
• B. ₹7637.1
• C. ₹1909.2
• D. ₹3818.5

Answer 1

The correct option is C ₹1909.2

Given :
Diameter(d) = 9 ft

$\text{Radius(r) =}\frac{d}{2}=4.5ft$

$\text{Area of circle =}𝛑r^2$

$=\frac{22}{7}\times 4.5\times 4.5$

$=63.6428sq.ft$

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> ∴Area of circle = 63.64 sq. ft

Given that, cost of painting per sq.ft is ₹ 30

Total cost for painting = Cost of painting per sq.ft x Area
= $30\times 63.64$
= ₹1909.2