# Mathematics 2009 | Study Mode

Question 41
A
180
B
120
C
110
D
40
##### Explanation
20 + 2x + 60 + 40 + x + 50 = 250
170 + 3x = 260
3x = 260 - 170
3x = 90
x = 90/3 = 30
At least 4 days
4 days = 40
5 days = 30
6 days = 50
Total = 120

Question 42
A
45
B
50
C
60
D
75
##### Explanation
Sectorial angle of apple
100 + 100 + 115 + x = 30o
315 + x = 360
x = 360 - 315
x = 45o
360o represents 400
1o represents 400 / 360
45o represents (400/360) x (45/1)
= 50 apples

Question 43
A
2/3
B
4/9
C
8/27
D
1/27
##### Explanation
P(pass) = 2/3
P(not pass) = 1 - 2/3 = 1/3
P(not passing any of the 3 Exams) = 1/3 x 1/3 x 1/3
= 1/27

Question 44
A
4
B
3
C
2
D
1
##### Explanation
 x f fx 5 3 15 8 2 16 6 4 24 k i k f=10 fx=55+k

 Mean = fx fx

 5.7 = 55+k 10

57 = 55 + k
k = 57 - 55
k = 2

Question 45
A
0.5
B
1
C
1.5
D
2
##### Explanation
 x x x-X /x-X/ x 1 -1 1 2x 2 0 0 x+1 2 0 0 3x 3 1 1 /x-X/=2

 Mean = x+2x+x+1+3x ____4

 2 = 7x+1 _4

8 = 7x+1
7x = 8-1
7x = 7
x = 1
 Mean deviation = /x-X/ __n

 = 2 4

 = 1 2

= 0.5

Question 46
A
15
B
28
C
30
D
45

Question 47
A
720
B
504
C
336
D
210
##### Explanation
 9P3 = _9! ways (9-3)!

 = 9! 6!

 = 9x8x7x6! ___6!

= 504 ways

Question 48