Question

A tank 12 m by 5 m is to be made. It is open at the top. Find the cost of iron sheet, at the rate of
12.00 per metre, if the sheet is 4 m wide.​

Answer 1

Answer:

3760

Step-by-step explanation:

Area of sheet = Surface area of the tank

Surface area of the tank = Area of 4 walls of the tank + Area of its base

A=20×8+8×12+20×8+8×12+20×2

A=160+96+160+96+240

A=752m  

2

 

Area of sheet = Surface area of the tank

L×2.5=752

L=300.8 m

Length of the sheet =300.8 m

∴ cost of the sheet =C=300.8×12.50

C=3760

Answer 2

Correct Question:

A tank 12 m long, 8 m wide and 5 m deep is to be made. It is open at the top. Find the cost of iron sheet, at the rate of Rs. 12 per metre, if the sheet is 4 m wide.

Given:

✰ Length of a tank = 12 m

✰ Breadth of a tank = 8 m

✰ Depth of a tank = 5 m

✰ Tank is open at the top.

To find:

✠ The cost of iron sheet, at the rate of Rs. 12 per metre, if the sheet is 4 m wide.

Solution:

Here in this question, first we will find of the sheet. The area of sheet is equal to the surface area of the tank. So, we will compare both of them and find the length of the sheet, then we will multiply the length of the sheet by the cost per metre to find the the required cost.

✭ Area of four walls = 2( l + b ) × h ✭

✭ Area of the base = l × b ✭

➛ Area of sheet = Area of four walls of the tank + area of the base of the tank

➛ Area of sheet = 2( l + b ) × h + l × b

Putting the values in the formula, we have:

➛ Area of sheet = 2( 12 + 8 ) × 5 + 12 × 8

➛ Area of sheet = 2 × 20 × 5 + 12 × 8

➛ Area of sheet = 40 × 5 + 12 × 8

➛ Area of sheet = 200 + 96

➛ Area of sheet = 296 m²

Now,

✭ Area of sheet = Surface area of tank ✭

➛ L × 4 = 296

➛ L = 296/4

➛ L = 74 m

∴ The length of sheet = 74 m

Now, find the required cost

➤ The cost of iron sheet per m = Rs. 12

➤ The cost of iron sheet per 74 m = Rs. 12 × 74

➤ The cost of iron sheet per 74 m = Rs. 888

∴ The cost of iron sheet = Rs. 888

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