Page 126 - Start Up Mathematics_7

3. Give the steps you will use to separate the variable and then solve the equation:

20p 3p
(a) 3n – 2 = 46 (b) 5m + 7 = 17 (c) 3 = 40 (d) 10 = 6
4. Solve the following equation:
(a) 2(x + 4) = 12 (b) 3(n –5) = 21 (c) 3(n – 5) = –21

(d) –4(2 + x) = 8 (e) 4(2 – x) = 8

Exemplar Problems

1. The value of y for which the expressions (y – 15) and (2y + 1) become equal is:
(a) 0 (b) 16 (c) 8 (d) –16
2. Which of the following equations can be formed starting with x = 0?
x
(a) 2x + 1 = – 1 (b) + 5 = 7 (c) 3x – 1 = – 1 (d) 3x – 1 = 1
2
3. ________ is the solution of the equation 3x – 2 = 7.
7
7
4. If x – = , then x = ________ .
8 8
9
5. is the solution of the equation 4x – 1 = 8. (True/False)
5
6. If 4x – 7 = 11, then x = 4. (True/False)
7. After 25 years, Rama will be 5 times as old as he is now. Find his present age.
8. One of the two numbers is twice the other. The sum of the numbers is 12. Find the numbers.

9. Radha gets ` 17,480 as her monthly salary and over-time. Her salary exceeds the over-time
by ` 10,000. What is her monthly salary?
10. The sum of three consecutive integers is 5 more than the smallest of the integers. Find the
integers.

11. In a bag, the number of one rupee coins is three times the number of two rupee coins. If the
worth of the coins is ` 120, find the number of one rupee coins.

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