Question

The diameter of a roller is 70 cm and its length is 1.5 m. It takes 1000 complete revolutions moving once over to level a stadium. Determine the area of the stadium
'P PLEASE DON'T SPAM IT'S VERY MUCH ARGENT'​

Answer 1

Given -

• Diameter of roller is 70 cm

• Length of roller is 1.5 m

• Number of revolutions is 1000

To find -

• Area of stadium

Formula used -

• Curved surface area of cylinder

Solution -

In the question, we are provided with the diameter, length of a roller and the number of revolutions it has taken, and we need to find the area of the stadium. For that first, we will convert the given diameter into Radius, by dividing it by 2, after that we will convert it into radius from m to cm. After that, we will find it's curved surface area, after that, we will solve the further question.

According to question -

• Length of roller = 1.5m = 150 cm

• Diameter = 70 cm

• Radius = 35 cm

Curved surface area of Cylinder -

• $\sf 2\pi rh$

On substituting the values -

$\sf \longrightarrow \: CSA \: = 2 \: \times \: \dfrac{22}{ \cancel{7}^{ \: \: 1} } \: \times \: \cancel{35}^{ \: \: 5} \: m \: \times 150 \: cm \\ \\ \sf \longrightarrow \: CSA \: = 2 \: \times \: 22 \: \times \: 5 \: cm \: \times \: 150 \: cm \\ \\ \sf \longrightarrow \: CSA \: = 33000 { \: cm}^{2}$

Now -

We will find the area of stadium by multiplying, the obtained curved surface area with number of revolutions.

Area of stadium = Curved surface area of roller × no. of revolutions .

$\sf \longrightarrow \: a \: = 33000 { \: cm}^{2} \: \times 1000 \\ \\ \sf \longrightarrow \: a \: = 33000000 { \: cm}^{2}$

$\therefore$ The area of the stadium is 33000000 cm²

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Answer 2

Answer:

Given :-

• Diameter = 70 cm
• Length = 1.5 m
• Revolution = 1000

To Find :-

Area

Solution :-

At first

$\sf \pink{R = \dfrac D2}$

$\sf \to \: R = \dfrac{70}{2}$

$\sf \to \: R = 35 \: cm$

Now

$\sf \pink{1 \: m= 100 \: cm}$

$\sf \to \: 1.5 \: m = (1 \times 100) + 50$

$\sf \to \: 1.5 \: m = 150 \: cm$

Now,

~ Finding CSA

$\sf \pink{CSA = 2\pi rh}$

$\sf \: CSA = 2 \times \dfrac{22}{7} \times 35 \times 150$

$\sf \: CSA = \dfrac{44}{7} \times 35 \times 150$

$\sf \: CSA = 44 \times 5 \times 150$

$\sf \: CSA = 220 \times 150$

$\sf \: CSA = 33000 \: c {m}^{2}$

Now

~ Finding Area

Area = CSA × 1000

Area = 33000 × 1000

Area = 33000000 cm²

Or,

Area = 33,000 m²