Page 324 - ICSE Math 8

Practice Time 11. (a) 3 (b) 7 (c) 15
3. (a) 5 (b) 40 (c) 60 (d) 32.5 (e) 10 12. (a) {A, I, C, T, R} (b) {D, O, N, Y} (c) {P, E}
6. (b) 31 (c) 69 (d) 11 (e) 5 (f) 27 students 10. 80% (d) {D, I, C, T, O, N, A, R, Y, P, E}
11. Max. run rate: 7 runs per over 13. (a) {–5, –3, –1, 0, 1, 3, 5, 6}
Min. run rate: 4 runs per over (b) {–6, –5, –3, –1, 0, 1, 2, 3, 5, 6}
Think Smart (c) {–5, –1, 0, 1, 3, 6}
1. (b) 2. 5 (d) {–5, –1, 0, 1, 3, 6}
Chapter 24 73 12 35+
14. 1 15. (a) (b) 11 213−
Exercise 17
3 1 1 1 1 1 Self-Testing Exercise 2
1. 2. (a) (b) (c) (d) (e)
5 4 4 4 2 2 1. 2 h 40 min 2. 32; 48; 64
1 1 15 5 2 1
3. (a) (b) (c) (d) (e) (f) 1
4 2 36 6 9 6 3. 6 days 4. 13 min 5. 23 % 6. ` 16,842
13
3 4 2 5 11 1
4. 5. 6. (a) (b) (c) (d) 7. ` 400 8. ` 484 9. ` 115.20
8 7 9 6 18 3
1 3 3 3 10. (a) ` 3,500 (b) ` 3,080 (c) 10%
7. (a) (b) (c) (d)
10 10 8 40 11. 4 : 5 12. 21
1
5
4
8. (a) (b) 9. 10. (a) 2 (b) 23 Self-Testing Exercise 3
9 9 3 25 25
4
3
2
3
2
Mental Maths 1. 18x + 24x + 27x + 20x + 10 (b) 11x – 19x – 7
1. (a) (iii) (b) (i) (c) (iii) (d) (iv) (e) (i) (c) + 9q (d) 54z – 13y
4
2. (a) False (b) True (c) True (d) False (e) True p p 2
1
3. (a) trial (b) 1 (c) 36 (d) (e) compound event 2. 14
2 3. (a) (13a – 2b)(2a – b) (b) 2y (x – 8y)(x + 8y)
2
Practice Time 3x + 1 2
8 59 4. ab(a – b); 750 5. x – 7 6. x = 3
1. P (doublet) = and P (not doublet) = 7. a = –2, 30
67 67
1 33 6 8. y < 10; y = {… 7, 8, 9}
2. (a) (c) (c)
2 100 25
9 4 5 6 7 8 9
l
(d) (Hint: If x is a number and x = a . b . c . ...., then
n
m
100
number of factors of x = (n + 1)(m + 1) (l + 1) ....) 9. 13, 15, 17 10. p(q + r)(q – r); 165
2
3 9 3 3 11. –12x + 11xy + 6x – 10y + 15y 2
3. (a) (b) (c) 4. 12. 4x – 14y + 5z + 3 13. (a) 104.04 (b) 96.04
4
2
10 20 4 5
1
1
1
5. (a) (b) (c) (d) 9 (e) 1 (f) 1 (g) 4 Self-Testing Exercise 4
2 2 4 26 13 52 13 1. x = 125; y = 35°; z = 20°
6. 2 or 1
14 7 2. 60°, 90°, 120°, 90°
Think Smart 5. Reflection in
1. 1 2. (a) Point
3 x-axis y-axis origin
Self-Testing Exercises (–3, –5) (–3, 5) (3, –5) (3, 5)
Self-Testing Exercise 1 (0, 7) (0, –7) (0, 7) (0, –7)
1. (a) 1 (b) –7 (c) –7 2. 12 < 203 < 107 < 59 < 7 (–2, 3) (–2, –3) (2, 3) (2, –3)
12 4 15 5 80 40 20 2
3. 1.12 4. 40; 43 5. 21 (4, –5) (4, 5) (–4, –5) (–4, 5)
6. –343 7. 19 8. 2
125 6. (–4, 3)
9. 3 10. (a) 4 (b) 6 (c) 8 9. 14 10. (a) 6 (b) 2 13. 24 cm
312