Page 315 - Start Up Mathematics_8 (Non CCE)

Some NCERT Textbook Questions

Find the values of the letters in each of the following and give reasons for the steps involved.
1. 4 A
+ 9 8
C B 3

2. 1 A
× A
9 A

3. A B
× 5
C A B

4. 2 A B
+ A B 1
B 1 8

5. If 21y5 is a multiple of 9, where y is a digit, what is the value of y?
6. If 31z5 is a multiple of 9, where z is a digit, what is the value of z?
You will find that there are two answers for the last problem. Why is this so?

Exemplar Problems

1. If 6A ¥ B = A 8 B, then the value of A – B is:
(a) –2 (b) 2 (c) –3 (d) 3

2. If B ¥ B = AB, then either A = 2, B = 5 or A = __________, B = __________.
3. If 213 x 27 is divisible by 9, then the value of x is 0. (True/False)
4. Suppose that the division x ∏ 5 leaves a remainder 4 and the division x ∏ 2 leaves a remainder 1. Find
the ones digit of x.
5. If 1AB + CCA = 697 and there is no carry over in addition, find the value of A + B + C.
6. Find the value of the letters in each of the following questions.

(a) A 0 1 B (b) 8 A B C
+ 1 0 A B – A B C 5
B 1 0 8 D 4 8 8

7. A three-digit number 2a3 is added to the number 326 to give a three-digit number 5b9 which is divisible
by 9. Find the value of b – a.
M A D
A S
8. Let D = 3, L = 7 and A = 8. Find the other digits in the sum.
+ A
B U L L

307