Question

the diameter of a circle is 77cm. How many revolution will it make to travel 121km?
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Answer 1

Answer:

If the diameter of a circle is 77 cm, then it takes 50000 revolutions to travel 121 km

Step-by-step explanation:

Given

Diameter of the circle = 77 cm = 2r

Here, r is the radius of the given circle

Distance traveled by the circle in 1 revolution = circumference of the circle

$=2\pi r$

Given 2r = 77 cm

So the circumference of the circle

$=77*\pi \\\\= 77 *\frac{22}{7} \\\\= 11*22\\\\=242cm$

So the number of revolutions for traveling 242cm = 1 revolution

Number of revolutions for traveling 121 km $=\frac{1}{242} *12100000$

= 50000 revolutions

(As 1km = 100000 cm, 121 km = 12100000cm)

Therefore, 50000 revolutions are taken by the circle to travel 121 km