Question

A square mesaures 80 yd on a side. Bob and Rob begin running from the same corner. Bob runs along a side to an adjacent corner, and Rob runs along a diagonal to an opposite corner. They arrive at their respective corners at the same time. If Bob's speed was 8mi/h, what was Rob's speed? Express your answer as a decimal to the nearest tenth.

Answer 1

c = 11.3 mi/h

Explanation:

Since Square has all of the same sides, hence bobs speed will be the same for all of the sides.

All of the sides are equal in a square

=> Let's consider the two sides along with the diagonal a right angled triangle

=>
`c^2 = a^2 + b^2`

Where c is the speed of Rob along the diagonal and b and c is the speed of Bob along the side

=>
`c^2 = 8^2+8^2`

=>
`c^2 = 64+64`

=>
`c^2 = 128\\`

Taking sq root on both sides

=> c = 11.3 mi/h