How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.
Find the variance of 2x, 2x-1 and 2x+1
2/3
2
√(2/3)
1
Correct answer is A
No explanation has been provided for this answer.
8
10
4
6
Correct answer is D
Black = 5
White = 4
Red = x
Total = 9+x
P(red) = 2/3
x / (9+x) = 2/5
5x = 2(9+x)
5x = 18+2x
5x-2 = 18
3x = 18
x = 6
If the mean of five consecutive integers is 30, find the largest of the numbers
28
30
32
34
Correct answer is C
Let the consecutive numbers be a, a+1, a+2, a+3, a+4
Mean = \(\frac{(a+a+1+a+2+a+3+a+4)}{5}\\
30 = \frac{5a+10}{5}\\
30 \times 5 = 5a + 10\\
5a = 150 - 10\\
5a = 140\\
a = 28 \\
∴ a + 4 = 28 + 4\\
= 32\)
15
20
30
45
Correct answer is A
The question will be answered in
\(^5C_4 = \frac{6!}{(6-4)!4!}\\=\frac{6!}{2!4!}\\=\frac{6\times5\times4!}{2\times1\times4!}\\=15\hspace{1mm}ways\)
1/20
1/3
3/20
7/10
Correct answer is C
U = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20}
A = {x/x is divisible by 2}
A = {2,4,6,8,10,12,14,16,18,20}
B = {x/x is divisible by 3}
A ∩ B = {6, 12, 18}
P(Number divisible by both 2 and 3)
= 3/20