word problem: how long did the entire trip take?

[kathleen66]

I some assistance with this one.

Bob roller blades 9 miles each morning. Today, he averaged 10mph for the first 6 miles but then slowed to 5mph for the remaining 3 miles. How long did the entire trip take?

Thanks

 

[stapel]

Use the standard "uniform rate" formula, "d = rt" (for "distance equals rate times time").

. . .first bit:
. . . . .distance: 6
. . . . .rate: 10
. . . . .time: 6/10 = 3/5 = 0.6

. . .last bit:
. . . . .distance: 3
. . . . .rate: 5
. . . . .time: ??

Complete the table to find the second time. Add the times to find the answer.

Eliz.