The length, breadth and thickness of a rectangular sheet of metal are 4.234 m, 1.005 m and 2.01 cm respectively. The area and volume of the sheet to correct significant figures are

detailed solution

Correct option is A

Given, length (l) = 4.234 mBreadth (b) =1.005 mThickness (t) =2.01cm =0.0201mArea of sheet (A)=2(ℓ×b+b×t+t×ℓ)=2[(4.234×1.005)+(1.005×0.0201)+(0.020×4.234​)]=2×43604739=8.7209478  m2As thickness has least number of significant figures 3, therefore rounding-off area up to three significant figures, we getArea of sheet (A)=8.72  m2Volume of sheet (V) = l × b × t=4.234×1.005×0.0201= 0.0855289Rounding-off up to three significant figures, we get  Volume of the sheet=0.0855  m3