NCERT Solutions for Class 7 Clat Chapter 4 Simple Equations

Complete the last column of the table.

Check whether the value given in the brackets is a solution to the given equation or not:

(a) n + 5 = 19 (n = 1) (b) 7n + 5 = 19 (n = − 2)

(c) 7n + 5 = 19 (n = 2) (d) 4p − 3 = 13 (p = 1)

(e) 4p − 3 = 13 (p = − 4) (f) 4p − 3 = 13 (p = 0)

Solve the following equations by trial and error method:

(i) 5p + 2 = 17 (ii) 3m − 14 = 4

Write equations for the following statements:

(i) The sum of numbers x and 4 is 9.

(ii) 2 subtracted from y is 8.

(iii) Ten times a is 70.

(iv) The number b divided by 5 gives 6.

(v) Three-fourth of t is 15.

(vi) Seven times m plus 7 gets you 77.

(vii) One-fourth of a number x minus 4 gives 4.

(viii) If you take away 6 from 6 times y, you get 60.

(ix) If you add 3 to one-third of z, you get 30.

Write the following equations in statement forms:

(i) p + 4 = 15 (ii) m − 7 = 3

(iii) 2m = 7 (iv) $\frac{m}{5}=3$

(v) $\frac{3m}{5}=6$ (vi) 3p + 4 = 25

(vii) 4p − 2 = 18 (viii) $\frac{p}{2}+2=8$

Set up an equation in the following cases:

(i) Irfan says that he has 7 marbles more than five times the marbles Parmit has. Irfan has 37 marbles. (Take m to be the number of Parmit’s marbles.)

(ii) Laxmi’s father is 49 years old. He is 4 years older than three times Laxmi’s age. (Take Laxmi’s age to be y years.)

(iii) The teacher tells the class that the highest marks obtained by a student in her class is twice the lowest marks plus 7. The highest score is 87. (Take the lowest score to be l.)

(iv) In an isosceles triangle, the vertex angle is twice either base angle. (Let the base angle be b in degrees. Remember that the sum of angles of a triangle is 180 degrees.)

Give first the step you will use to separate the variable and then solve the equation:

(a) x + 1 = 0 (b) x + 1 = 0 (c) x − 1 = 5

(d) x + 6 = 2 (e) y − 4 = − 7 (f) y − 4 = 4

(g) y + 4 = 4 (h) y + 4 = − 4

Give first the step you will use to separate the variable and then solve the equation:

(a) 3l = 42 (b) $\frac{b}{2}=6$ (c) $\frac{p}{7}=4$

(d) 4x = 25 (e) 8y = 36 (f) $\frac{z}{3}=\frac{5}{4}$

(g) $\frac{a}{5}=\frac{7}{15}$ (h) 20t = − 10

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

(a) 3n − 2 = 46

(b) 5m + 7 = 17

(c) $\frac{20p}{3}=40$

(d) $\frac{3p}{10}=6$

Solve the following equations:

(a) 10p = 100 (b) 10p + 10 = 100 (c) $\frac{p}{4}=5$

(d) $\frac{-p}{3}=5$ (e) $\frac{3p}{4}=6$ (f) 3s = − 9

(g) 3s + 12 = 0 (h) 3s = 0 (i) 2q = 6

(j) 2q − 6 = 0 (k) 2q + 6 = 0 (l) 2q + 6 = 12