1. A square room contains 180 cu. metre of air. The cost of plastering its four walls at Rs 20 per sq.
metre is Rs 2,400. Find the height of the room.[Ans:5m]
2. After destruction by massive earthquake, the wall of length 40 m, height 5 m and width 20 cm was
reconstructed. It contains two windows each of 2 m × 1.5 m and a gate of size 1.5 m × 4 m. (i) Find the
number of bricks each of 25 cm × 20 cm × 4 cm required to construct the wall. (ii) Find the cost of the
bricks at the rate of Rs 16,000 per 10000 bricks. [Ans: (i) 23,500 (ii) Rs 3,76,000 ]
3. Mr. Gurung constructed a compound wall 40 m long and 20 cm wide by the bricks, each measuring 20
cm × 10 cm —5 cm. If he paid Rs 4,32,000 at the rate of Rs 18,000 per 1000 bricks, find the height of the
wall ? [Ans: 3m]
1. 9a4 + 14a2 + 25
2. a4 b
4 + a2 b
2 + 1
3. x4
y
4 + 1 + y
4
x
4
4. p6 – 1
5. x2 – 10x + 16 – 6y – y
2
6. (9 – a
2
) (100 – b
2
)
7. 6(a + b)2 – (a + b) – 7
8) 2x 2
/ y – 3 – 5y2
/ x
9In a class of 40 students, 3 boys and 5 girls wear spectacles. If a teacher called one of the students
randomly in the office, find the probability that this student is wearing the spectacle.
10. There are 40 students in a class with roll numbers from 1 to 40. The roll number of Bhurashi is 18. If
a teacher calls one student with roll number exactly divisible by 3 to do a problem on blackboard, what
is the probability that Bhurashi will be selected? Also, find the probability that she will not be selected.
11. A card is drawn at random from a well shuffled pack of 52 cards. Find the probability that the card
will be black or face cards
13. One card is drawn at random from the number cards numbered from 10 to 21. Find the probability
that the card may be prime or even numbered card
14. Define sample space. What is the probability of a certain event?
15. A die is rolled once. What is the probability that the digit turn off is a prime number.
16. A bag contains a dozen of identical balls. Among them, 3 are red, 5 are greed and the rest are white.
If a ball is randomly drawn, what is the probability of getting the white ball?
17. A card is drawn at random from a well shuffled pack of 52 cards. Find the probability that the card
will be black king or red queen.
18. Three athletes A, B and C are to run a race. If A is twice as likely to win B and B is thrice as likely to
win C. Find the probability of each athlete winning