Math, asked by 4351bestfriend, 2 months ago

metal piece is 28 cm long and has an external radius of 2.1 CM if its thickness is 0.7 CM then find the whole surface area of the pipe x

Answers

Answered by Anonymous
1

Answer:

PSP~

Step-by-step explanation:

Here, l = 1.5 m, b = 1.25 m

∵ It is open from the top.

∵ Its surface area = [Lateral surface area] + [Base area]

= [2(l + b)h] + [l × b]

= [2(1.50 + 1.25)0.65 m2] + [1.50 × 1.25 m2]

= [2 × 2.75 × 0.65 m2] + [1.875 m2]

= 3.575 m2 + 1.875 m2 = 5.45 m2

∵ The total surface area of the box = 5.45 m2

∴ Area of the sheet required for making the box = 5.45 m2

(ii) Rate of sheet = Rs. 20 per m2

Cost of 5.45 m2 = Rs. 20 × 5.45

⇒ Cost of the required sheet = Rs.109

Q2. The length, breadth and height of a room are 5m, 4m and 3m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate off 7.50 per m2.

Sol: Length of the room (l) = 5m

Breadth of the room (b) = 4 m

Height of the room (h) = 3 m

The room is like a cuboid whose four walls (lateral surface) and ceiling are to be white washed.

∴ Area for white washing = [Lateal surface area] + [Area of the ceiling]

= [2(1 + b)h] + [1 × b]

= [2(5 + 4) } 3 m2] + [5 × 4 m2]

= [54m2] + [20m2] = 74m2

Cost of white washing:

Cost of white washing for 1 m2 = Rs. 7.50

∴ Cost of white washing for 74 m2 = Rs. 7.50 × 74

The required cost of white washing is Z555.

Answered by tejasfuse
2

Answer:

Solution: Total surface area=CSA of outside cylinder+ CSA of inside cylinder+2*area of ring. `=2piRh+2pirh+2pi(r^2-r^2)` `=2pi(25/2h+23/2h+(25/2+23/2)(25/2-23 ..

Please mark this answer as Brainiest answer...

Hope you understand...

Similar questions