Bryan Yeo's answer to Gamin's Primary 6 Maths Speed Singapore question.

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Bryan Yeo
Bryan Yeo's answer
26 answers (Tutor Details)
1st
Note:increased speed->Usual speed+30km/h)->2hours
Usual speed->2 and 3/4hours
So,30km/h x2 hours is the difference
in the distance of the 2 speeds when
The increased speed have reached(2h).
Usual speed takes 3/4hour to cover
A distance of 60km so it is (60x4/3)km/h
Which is equal to 80km/h.

45 minutes=3/4hours.