Question

Take -
The radius of a wheel of a cycle is 70 cm and it takes 5 minutes to make 300 rotations Find the
speed of the cycle in km per hour. (Take pie
22/7 )​

Answer 1

Given:

• the radius of a wheel of cycle = 70cm
• time taken by wheel to make 300 rotation = 5min

To Find:

speed of the cycle in km per hour

Solution:

$\sf{radius = 70cm}$

$\sf \: distance \: covered \: in \: one \: revolution:$

${ \color{orange} {\boxed{ \sf{circumference \: of \: the \: wheel \: = 2\pi r}}}}$

$\implies\sf{ 2 × \frac{22}{7} × 70}$

$\implies\sf{440cm}$

$\sf{⊱\:distance\: covered\:in\:300\: rotation\:=\:300\:×\:440}$

$\implies\sf{132000}$

$\implies\sf{ \frac{132000}{100000}\:=\:1.32km}$

It is given that:

distance of 1.32km is covered in 5 mins or $\sf{ \frac{5}{60}}$hours

Therefore,

speed of cycle $\sf{=\: \frac{distance}{time}}$

$\implies\sf \: { \frac{1.32}{ (\frac{5}{60})}}$

$\implies\tt{\frac{1.32 \times60 }{5}}$

$\implies\tt{15.84\:km/hr}$

Hence,

speed of the cycle in km per hour is $\sf\color{purple}{15.84\:km/hr}$

Answer 2

Answer:

15.84

this is the answer