Exercise: Volume And Surface Area

Questions for: Volume And Surface Area

What is the volume of 32 metre high cylindrical tank?

I. 

The area of its base is 154 m2.

 II. 

The diameter of the base is 14 m.

A:
I alone sufficient while II alone not sufficient to answer
B:
II alone sufficient while I alone not sufficient to answer
C:
Either I or II alone sufficient to answer
D:
Both I and II are not sufficient to answer
Answer: C

Given, height = 32 m.

I gives, area of the base = 154 m2.

Volume = (Area of the base x Height) = (154 x 32) m3.

Thus, I alone gives the answer.

II gives, radius of the base = 7 m.

Volume = r2h = 22 x 7 x 7 x 32 m3 = 4928 m3.
7

Thus, II alone gives the answer.

Correct answer is (C).

📖
📝
💬
👁️
How many bricks, each measuring 25 cm x 11.25 cm x 6 cm, will be needed to build a wall of 8 m x 6 m x 22.5 cm?
A:
5600
B:
6000
C:
6400
D:
7200
Answer: C

Number of bricks = Volume of the wall = 800 x 600 x 22.5 = 6400.
Volume of 1 brick 25 x 11.25 x 6

📖
📝
💬
👁️
A large cube is formed from the material obtained by melting three smaller cubes of 3, 4 and 5 cm side. What is the ratio of the total surface areas of the smaller cubes and the large cube?
A:
2 : 1
B:
3 : 2
C:
25 : 18
D:
27 : 20
Answer: C

Volume of the large cube = (33 + 43 + 53) = 216 cm3.

Let the edge of the large cube be a.

So, a3 = 216         a = 6 cm.

Required ratio = 6 x (32 + 42 + 52) = 50 = 25 : 18.
6 x 62 36

📖
📝
💬
👁️
What is the total surface area of a right circular cone of height 14 cm and base radius 7 cm?
A:
344.35 cm2
B:
462 cm2
C:
498.35 cm2
D:
None of these
Answer: C

h = 14 cm, r = 7 cm.

So, l = (7)2 + (14)2 = 245 = 75 cm.

Total surface area = rl + r2
= 22 x 7 x 75 + 22 x 7 x 7 cm2
7 7
= [154(5 + 1)] cm2
= (154 x 3.236) cm2
= 498.35 cm2.

📖
📝
💬
👁️
A cistern of capacity 8000 litres measures externally 3.3 m by 2.6 m by 1.1 m and its walls are 5 cm thick. The thickness of the bottom is:
A:
90 cm
B:
1 dm
C:
1 m
D:
1.1 cm
Answer: B

Let the thickness of the bottom be x cm.

Then, [(330 - 10) x (260 - 10) x (110 - x)] = 8000 x 1000

320 x 250 x (110 - x) = 8000 x 1000

(110 - x) = 8000 x 1000 = 100
320 x 250

x = 10 cm = 1 dm.

📖
📝
💬
👁️
Ad Slot (Above Pagination)
Quiz