# A boy is cycling such that the wheels of the cycle are making 140 revolutions per minute. Ifthe diameter of the wheel is 60 cm, calculate the speed per hour which the boy is cycling.

Radius of the wheel = r = 60 / 2 = 30 cm

Circumference of the wheel = 2 Π r = (2 x 22 / 7 x 30) cm = 1320 / 7 cm

=> Distance covered by the wheel in 1 revolution = 1320 / 7 cm

=> Distance covered by the wheel in 140 revolutions = 1320 / 7 x 140 cm

= (1320 / 7 x 140 x 1 / 100000) km = 264 / 1000 km

This means that distance covered by the wheel in 1 minute = Distance covered in 140 revolutions

= 264 / 1000 km

Therefore, Distance covered in 1 hour = 264 / 1000 x 60 km = 15.84 km

Hence, the speed with which the boy is cycling is 15.84 km / hr

• 142

guess tis s rite.If its wrong pls let me know!!!!!!!

• 2

juy

• -18
It is right sreenidhi ...!!! 😄😄😄😄
• 2
its ryt
• -1
15.84km/hr
• 7
wrong

• -26
15.6

• -23
Hope this helps you 😃😃 And yes thumbs up • 70
See ans
• -15
• -1
15.84 km per hr
• -1
??Radius of the wheel = r = 60 / 2 = 30 cm

Circumference of the wheel = 2 ? r = (2 x 22 / 7 x 30) cm = 1320 / 7 cm

=> Distance covered by the wheel in 1 revolution = 1320 / 7 cm

=> Distance covered by the wheel in 140 revolutions = 1320 / 7 x 140 cm

= (1320 / 7 x 140 x 1 / 100000) km = 264 / 1000 km

This means that distance covered by the wheel in 1 minute = Distance covered in 140 revolutions

= 264 / 1000 km

Therefore, Distance covered in 1 hour = 264 / 1000 x 60 km = 15.84 km

Hence, the speed with which the boy is cycling is 15.84 km / hr
• 2
Ana is 15.84
• -1
🐅
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I think it is correct • 1
Diameter of wheel=60cm Radius of wheel=60/2=30cm Number of revolution made=140 Time taken in making 140revolution =1minute Distance covered in one revolution=the circumference of the wheel=2πr =2πr × 140 =1320/7 × 140 =26400cm =26400/100m =264/1000km =0.264km Distance covered by the wheel in one minute=0.264km Distance covered by the wheel in 1hr =0.264×60 =15.84 km
• 2
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