Question

How many coins 7 cm in diameter and thickness 1 cm must be melted
to form a cuboid of dimensions 80 cm x 15.4 cm x 10 cm?​

Answer 1

Step-by-step explanation:

Coins are in the shape of cylinder

Therefore=22/7*7/2*7/2*1

=38.5cm3

Therefore no.of coins=80*15.4*70/38.5

=320coins

Answer 2

Answer:

320

Step-by-step explanation:

volume of one coin = π(7/2)²(1)

= π(7/2)²cm³

= 22/7×7/2×7/2

= 77/2cm³

volume of cuboid = 80×15.4×10cm³

so, no of coins should be melted =

(80×15.4×10)/(77/2)

= (80×154×2)/77

= 80×2×2

=> 320 .....ans.