Page 153 - ICSE Math 6

MENTAL MATHS

1. Which of the following equations are linear?
1
2
(a) 3x + 9 = 5 (b) 4x + 2y = 6 (c) x + y = 12
3 4
4
2
(d) 5x – 5 = 10x – 15 (e) x – 2 = 3x + 5 (f) 4x + 10x = 6
2. Fill in the blanks.
(a) If x = y, then x + 9 = y + __________ (b) If x = y, then x – 5 = __________ – 5
x
(c) If x = y, then 3x = __________ (d) If x = y, then = __________
10
3. Match the statements with their algebraic forms.
Statement Algebraic Form
(a) Three added to x gives 7. (i) m = 32
8
(b) Thrice of y minus 4 is 6. (ii) x + 32 = 56
(c) A number when divided by 8 gives 32. (iii) x + 3 = 7

(d) The sum of x and 32 is 56. (iv) 4n = 6
(e) A number when multiplied by 4 gives 6. (v) 3y – 4 = 6

PRACTICE TIME

1. Express each of the following statements in algebraic form.

(a) A number when multiplied by 3 gives 27.
(b) 13 subtracted from twice of y is equal to 11.
(c) Twice of a number when added to 5 gives one-third of the same number.

(d) The sum of three consecutive numbers is 33.
2. Write suitable statements for the following algebraic expressions.
2
(a) 3z – 4 = 6 (b) 4y + 5 = y (c) 1 x + 9 = 7
5 3
5
(d) = 29 (e) 7x + 2 = 0 (f) 8 + x = 6
y
3. Solve.

(a) x + 10 = 12 (b) y – 5 = 2
− 2 8 a 3
32
(c) z = (d) +=
3 9 10 5
(e) 2(2x + 1) – 4(x + 1) = 2(x – 3) (f) 6(z – 3) + 9(z + 2) = –11z
(g) 3x – x + 5 = 10 (h) 3a + 2(5a – 10) = 6a – 6
4. Solve the following and verify the solution.

(a) 4(a – 4) = 4 (b) 5 = 2(a – 2) (c) 4(x – 3) = 2x + 4
1 1 –4 1
(d) –11(x – 1) = 2x (e) (z + 5) = 2 (f) (x + 2) = –5x +
3 3 5 5

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