The number of coins 1.5 cm in diameter and 0.2cm thick to be melted to form a right circular cylinder of height 10 cm and diameter 4.5 cm is
a. 380
b. 450
c. 472
d. 540

• let be n coins
  so, n*vol of each coins=vol of cylinder
  n*pi*(1.5/2)^2*0.2=pi*(4.5/2)^2*10
  n=450
• 10 years agoHelpfull: Yes(2) No(1)
• 450
  volume of coin 22/7*0.758*0.75*0.2
  volume of cylinder 22/7*2.25*2.25*10
  cylinder/coin=450
• 6 years agoHelpfull: Yes(0) No(0)
• Volume of 1 coin = 22/7 *(1.5)/2*(1.5)/2 * 0.2 = 99/280 cm3
  
  Volume of large cylinder = 22/7 *(4.5)/2*(4.5)/2 * 10 = (99*45)/28cm3
  
  Number of coins = (99*45)/28 * 280/99 = 450
• 6 years agoHelpfull: Yes(0) No(0)