# pre-algerbra

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I have been working on this problem for an hour and a half! I keep getting 1.33 but I know that's not right!!
Jim drove the 120 miles to grandmothers house in 3 hours. He increased the speed by 10 miles per hour on the way home. How long did it take him to drive home?

• pre-algerbra -

velocity on the way: 120/3 mph

veloicyt on the way back: 120/3 + 10

time to get back: distance/velocity
= 120/(50)=12/5=2 2/5 hrs

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