Question

Q7. Find the number of coins, 2.5 cm in diameter and 0.4 cm thick, to be
melted to form a right circular cylinder of height 10 cm and diameter 4 cm.​

Answer 1

$\huge{\fbox{\fbox{\orange{\mathfrak{Answer\::}}}}}$ 320

Step-by-step explanation:

• Volume of cylinder = πr²×h
• ➡No. of coins=Volume of cylinder/volume of coins
• ➡️3.14×(10)²×2/3.14×(1.25)²×0.4
• ➡️100×2/1.5625×0.4
• ➡️200/.625
• ➡️320

Therefore, 320 coins required