A large metal ball with a radius of 15 cm is melted down to make smaller metal balls with a radius of 5 cm. How many of these smaller metal balls can be made?
2 Answers
Large metal ball =4/3 (π)(r^3) with r = 15 cm
=4/3*3.142*15^3 =14139 cm^3
Small metal ball = 4/3 (π)(r^3) with r = 5 cm
=4/3*3.142*5^3 =523.667 cm^3
Number of Small Metal Balls = 14139 / 523.667 = 27 Balls
Volume of a large metal ball with R = 15 cm is equal to volume of x metal ball with r = 5 cm
So,
4/3 (π)(R^3) = 4/3 (π)(r^3)(x)
x = (R^3) / (r^3)
= (15^3) / (5^3)
= (15/5)^3
= 3^3
= 27
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