Question

3. How many minutes are saved by travelling 30 km at 90 km/h instead 80 km/he?​

Answer 1

4.5 minutes minutes are saved by travelling 30 km at 90 km/h instead 80 km/h

Step-by-step explanation:

GIVEN

Distance = 30 km

Speed 1 = 90 kk/h

Speed 2 = 80 km/h

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TO FIND

How many minutes are saved by travelling 30 km at 90 km/h instead 80 km/h

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FORMULAS

Speed = Distance / Time

Distance = Speed × Time

Time = Distance / Speed

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We know that,

Time = Distance / Speed

Time = 30 / 90

Time = 0.3

Time = 0.3 hours

Time = 18 minutes

30 km at speed of 90 km/h will travel in 18 minutes

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We know that,

Time = Distance / Speed

Time = 30 / 80

Time = 0.375

Time = 0.375 hours

Time = 22.5 minutes

30 km at speed of 80 km/h will travel in 22.5 minutes

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Now

Let's find how many minutes are saved

Saved Time = 22.5 minutes - 18 minutes

Saved Time = 4.5 minutes

Saved Time = 4.5 minutes

4.5 minutes minutes are saved by travelling 30 km at 90 km/h instead 80 km/h