Question

From a rectangular cardboard sheet 145 cm long and 32 CM broad 42 circular plates each of diameter 8 cm have been cut out find the area of remaining portion of the sheet

Answer 1

heya!

here's ur answer...

given the length of the cardboard sheet is 145cm and breadth is 32cm

hence area of the cardboard=l×b

=145×32

=4640cm²

diameter of one circle which has been cut out from the sheet=8cm

therefore radius=8/2

=4cm

area of one circle=πr²

=22/7×4×4

=352/7cm²

therefore area of 42 such circles=352/7×42

=14784/7

=2112cm²

thus area of the remaining sheet=4640-2112

=2528cm²

hope this helps...!

Answer 2

Area Of Remaining Portion = Area Of CardBoard - 42 × Area Of Each Circle

Therefore,

Area Of CardBoard =

LENGTH × BREADTH

145 × 32

$4640 {cm}^{2}$
____________________________________

Area Of Each Circle =

$\pi {r}^{2}$
Given,

Diameter = 8cm

Therefore, Radius = 4cm

Therefore,
(assuming
$\pi$be 22/7)

= 22/7 × 4 × 4 × 42

=2112cm^2

=$2112 {cm}^{2}$
Therefore,

Area Of Remaining Portion = Area Of CardBoard - 42× Area Of Each Circle

=4640 -2112
= $2528 {cm}^{2}$
Therefore, The Area Of the Remaining Portion =
$2528 {cm}^{2}$
Hope this helps !