First note that; half an hour is equivalent to 30 minutes and an hour = 60 minutes.

So, if 1 hour = 60 minutes, then 1.5 hours =?

= (1.5/1) x 60

= 1.5 x 60

= 90

Therefore; there are 90 minutes in 1 and a half hours.

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Or

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Simple add directly if I hour=60 minutes and half hour = 30 minutes, then

= 60 + 30

= 90

1.5 hours = 90 minutes.

Well you know that there are 60 min/hr and you are trying to find how many minutes in 1.5 hr. It is real simple, just multiply how many hours you have by the conversion factor. In this case you have 1.5 hr and your conversion factor is 60 min/hr. You should set it up something like this

(1.5hr)(60min/hr) = 90 min

Because the hours cancel out you are left with your answer in minutes

There are 60 minutes in one hour, so in one half hour there are 30 minutes. In one and a half

hours, there are 60 + 30 = 90 minutes.

There are 90 minutes in an hour and a half. 1 hour equals 60 minutes, half an hour equals 30 minutes, so 60 plus 30 equals 90 minutes.

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