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Question

Two students were racing home from school. Eric rides his skateboard and Robby rides his bicycle. Eric leaves 40 seconds before Robby. Eric traveled at a speed of 10 feet per second. Robby traveled at a speed of 30 feet per second. For how many seconds had Eric traveled when the both boys were the same distance from school?

Answer 1

Shontacilla, we know that distance = speed x time. Since the distances are the same, we can set each speed x time equal to each other.

 

If we let s = the number of seconds...

 

10(s + 40) = 30s

 

Eric travelled for 40 more seconds, according to the problem.

 

If we distribute...

 

10s + 400 = 30s

400 = 20s

s = 20

 

So, Robby travelled for 20 seconds, which means that Eric travelled for 60.

 

Hope this helps!