Question

I road roller is 350cm long and it diameter is 84cm.
it takes 500 complete revolutions to travel the road. The area covered by it in
m2 will be a) 4 620
b) 6420
c) 2460
d) 4260​

Answer 1

Answer:

c

Explanation:

I am not sure if you have any questions or need any further information

Answer 2

Given :

A road roller is 350 cm long

Diameter is 84 cm

Road roller makes 500 revolution to level the road.

To Find :

Area covered by road roller in meter square (m²)

Solution :

✪ Let's calculate the radius of the roller.

Diameter : 84 cm

$\longrightarrow \: radius(r) = \frac{diameter}{2}$

$\longrightarrow \: r = \frac{84}{2} = 42cm$

•°• Radius of the roller = 42 cm.

✪ Curved Surface Area :

We can calculate the CSA using the formula,

$\large { \boxed{ \rm{ \red{curved \: surface \: area = 2\pi \: rh}}}}$

$\mathtt \longrightarrow csa = 2 \times \frac{22}{7} \times 42 \times 350$

$\mathtt \longrightarrow csa = \frac{44}{7} \times 14700$

$\mathtt \longrightarrow csa = 44 \times 2100 = 92400$

$\large{ \boxed{ \mathtt { \blue{curved \: surface \: area = 92400cm {}^{2} }}}}$

✪ The roller makes 500 revolutions to level the road.

•°• Area covered in 500 revolutions will be CSA times the number of revolutions.

$\mathtt \longrightarrow 92400 \times 500 = 46200000$

$\large { \boxed{ \mathtt { \green{area \: covered \: in \: 500 \: revolutions = 46200000m {}^{2} }}}}$

✪ We have to find the area covered by roller in m²

•°• Multiply 100 times 100 and divide the area covered in 500 revolutions in cm² from the result obtained i.e 10000.

✪ AREA COVERED IN m² :

$\longrightarrow \frac{46200000}{10000}$

$\longrightarrow4620$

$\large{ \boxed { \mathtt{ \pink{area \: covered \: in \: 500 \: revolutions \: in \: meter = 4620 {}^{2} }}}}$