June 2020

Class 8 – Mathematics Playing with Numbers – Exercise 16.1 Find the values of the letters in each of the following and give reasons for the steps involved. Question :1. Answer : On putting A = 1, 2, 3, 4,…

Class 8 – Mathematics Introduction to Graphs – Exercise 15.3 Question :1. Draw the graphs for the following tables of values, with suitable scales on the axes. (a) Cost of apples No. of apples 1 2 3 4 5 Cost…

Class 8 – Mathematics Introduction to Graphs – Exercise 15.2 Question :1. Plot the following points on a graph sheet. Verify if they lie on a line (a) A(4,0), B(4,2), C(4,6), D(4, 2.5) (b) P(1,1), Q(2,2), R(3,3), S(4,4) (c) K(2,…

Class 8 – Mathematics Introduction to Graphs – Exercise 15.1 Question :1.The following graph shows the temperature of a patient in a hospital, recorded every hour: (a) What was the patient’s temperature at 1 p.m.? (b) When was the patient’s…

Class 8 – Mathematics Factorisation – Exercise 14.4 Find and correct the errors in the following mathematical statements: Question : 1. 4(𝓍 − 5) = 4𝓍 − 5 Answer : L.H.S. = 4(𝓍 − 5) = 4𝓍 − 20 ≠…

Class 8 – Mathematics Factorisation – Exercise 14.3 Question :1. Carry out the following divisions: (i) 28𝓍4 ÷ 56𝓍 (ii) −36y3 ÷ 9y2 (iii) 66pq2r3 ÷ 11qr2 (iv) 34𝓍3y3z3 ÷ 51𝓍y2z3 (v) 12a8b8 ÷ (−6a6b4) Answer : Question :2. Divide…

Class 8 – Mathematics Factorisation – Exercise 14.2 Question :1. Factorize the following expressions: (i) a² + 8a + 16 (ii) p² − 10p + 25 (iii) 25m² + 30m + 9 (iv) 49y² + 84yz + 36z² (v) 4𝓍²…

Class 8 – Mathematics Factorisation – Exercise 14.1 Question :1. Find the common factors of the given terms. (i) 12x, 36 (ii) 2y, 22xy (iii) 14pq, 28p²q² (iv) 2x, 3x², 4 (v) 6abc, 24ab², 12a²b (vi) 16x³, −4x², 32x (vii)…

Class 8 – Mathematics Direct and Inverse Proportions – Exercise 13.2 Question : 1. Which of the following are in inverse proportion: (i) The number of workers on a job and the time to complete the job. (ii) The time…

Class 8 – Mathematics Direct and Inverse Proportions – Exercise 13.1 Question : 1.Following are he car parking charges near a railway station up to: 4 hours Rs.60 8 hours Rs.100 12 hours Rs.140 24 hours Rs.180 Check if the…

Class 8 – Mathematics Exponents and Powers – Exercise 12.2 1. Express the following numbers in standard form: (i) 0.0000000000085 (ii) 0.00000000000942 (iii) 6020000000000000 (iv) 0.00000000837 (v) 31860000000 Answer : (i) 0.0000000000085 = 0.0000000000085 x 1012⁄1012 = 8.5 x 10-12…

Class 8 – Mathematics Exponents and Powers – Exercise 12.1 1. Evaluate: Answer : 2. Simplify and express the result in power notation with positive exponent: Answer : 3. Find the value of: Answer : 4. Evaluate: Answer : 5.…