Question

I need the answer please and can u answer my recent to.

Answer 1

30 hours.

Explanation:

Richard can build 15 snowballs in 1 hour

But 2 snowballs melt every 15 minutes

In 1 hour, the number of snowballs that will have melted is:

`(60)/(15)` × 2 = 8

The number of snowballs that will have remained = 15 - 8 = 7

So 7 snowballs will have remained in 1 hour

For 210 snowballs to have remained, it will take:

`(210)/(7)` × 1 = 30 hours.