Step: 1
Let r be the increase in radius of the snowball (in inches).
Step: 2
101 = 40r
[Write the proportion in terms of feet/inches.]
Step: 3
10 × r = 1 × 40
[Write the cross products.]
Step: 4
Step: 5
10r10 = 4010
[Divide both sides by 10.]
Step: 6
Step: 7
The radius increases by 4 in.
Step: 8
The final radius of the snowball = Initial radius + Increase in radius = 6 + 4 = 10 in.
Step: 9
So, the radius of the snowball after it travels 40 ft is 10 in.
Correct Answer is : 10 in.