Geometry, geometry, geometry !

Question

Mimie left home on her bicycle at an average rate of 6 km/hr. One hour later, her sister Yolly set out to overtake her at an average rate of 8 km/hr. In how many hours will Yolly overtake her sister?

Answer 1

i say it is 4 hours because in three hours, yolly will tie her with 24km.

then the next hour, she will overtake her with 32km. mimie will only have 30km

peace...

Answer 2

4 hours

Mimie goes 24 km in 4 hours

Yolly goes 24 km in 3 hours, but she is an hour behind

so 4 hours

Answer 3

Hi dan_vice

Yolly overtake her sister in 45 minutes.

Answer 4

not absolutely sure but i think this might help you find the answer. (Haven't been in geometry for 3 years.)

in 3 hours Yolly could have gone 24km.

and in 3 hours Mimie would have only gone 18km.

Hope that helps...if not and it only confuses you more. I apologize.  

Answer 5

I wouldn't call this geometry, but here goes:

Minnie's rate=6 km/h

Yolly's rate    =8km/h

d=rt

in the end the d will be the same, so set the two equal

8km(h-1)=6km(h)

factor out the km

8(h-1)=6(h)

8h-8=6h

2h=8

h=4

Answer 6

The hour after Mimie leaves, she is six km ahead of Yolly (Yolly hasn't moved yet). An hour after that, she is only four km ahead of Yolly (who has now moved 8 km), then another and two, another and nothing; so Yolly overtakes her in the span of three hours after she leaves.