Exercise 15C
Question 1
(a) 5, 3, 5, 2, 3, 5, 17
Mode – 5
(b) 1, 7, 13, 19, 25
= No Mode
(c) 4, 6, 8, 4, 10, 4, 6, 12, 6, 10
= Modes – 4, 6
(d) 51, 68, 70, 76, 55, 70, 73, 68, 70, 81
= Mode – 70
(e) 8, 4, 8, 4, 8, 4, 8, 4, 8, 4, 8, 4
= Modes – 8, 4
(f) 29, 29, 10, 10, 3, 3, 14, 10, 2, 2
= Mode – 10
(g) 26, 32, 26, 21, 83, 26, 83, 67, 53, 83, 85
= Modes – 26, 83
Question 2
(a)
| Size | 2 | 3 | 4 | 5 | 6 | 7 |
| Frequency | 4 | 6 | 2 | 5 | 3 | 1 |
Mode – 3
(b)
| Size of shoes | 6 | 7 | 8 | 9 | 10 |
| No. of persons | 12 | 20 | 40 | 15 | 7 |
Mode – 8
Question 3
(a) 1, 6, 8, 11, 11, 11, 14, 16, 21
(i) The mode = 11
(ii) The median = 11
(iii) The mean $=\frac{(1+6+8+11+11+11+14+16+21)}{9}$
$=\frac{99}{9}$
= 11
(b) 3,10,10,12,14,16,16,18,18,25
(i) The mode=10,16,18
(ii) The median $=\frac{1}{2} \left(14+16\right)$
$=\frac{1}{2} \times 30$
=15
(iii) The mean $=\frac{3+10+10+12+14+16+16+18+18+25}{10}$
$=\frac{142}{10}$
=14.2
(c) 2,6,9,11,15,23,29,36,42
(i) No mode
(ii) The median =15
(iii) The mean$=\frac{2+6+9+11+15+23+29+36+42}{9}$
$=\frac{173}{9}=19\frac{2}{9}$
(d) 8,8,8,8,18,18,18,18
(i) The mode=8, 18
(ii) The median $=\frac{1}{1} (8+18)$
$=\frac{1}{2} \times 26$
=13
(iii) The mean $=\frac{8+8+8+8+18+18+18+18}{8}$
$=\frac{104}{8}$
=13
Question 4
Number of fiction books read by 28 grade VII pupils:
4,6,1,7,3,9,5,7,8,5,4,6,10,6,9,5,6,6,8,6,8,5,10,7,2,5,3,7
Mode = 6
Mean $=\frac{ (4+6+1+7+3+9+5+7+8+5+4+6+10+6+9+5+6+6+8+6+8+5+10+7+2+5+3+7)}{25}$
$=\frac{168}{28}$
= 6
Question 5
20,21,19,22,18,23,25,22,23,20,23,20,22,21,24,21,22,23,19,21,22,22,24,26,22
Mode = 22
Mean $=\frac{(20+21+19+22+18+23+25+22+23+20+23+20+22+21+24+21+22+23+19+21+22+22+24,26+22)}{25}$
$=\frac{550}{25}$
= 22
Question 6
(a) T
(b) F
(c) T
No comments:
Post a Comment