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.
The variance of x, 2x, 3x, 4x and 5x is
x√2
2x2
x2
3x
Correct answer is B
Hint: prepare a three-columned table, one for (x), another for the (deviation), and the last for the (squared-deviation).
Sum of (x) = 15x, algebraic sum of (deviation) = zero (0)
Sum of (squared-deviation) = 10x2
Variance = ∑(squared-deviation)/n = 10x2/5 = 2x2
3/4
3/10
1/4
1/20
Correct answer is A
U = {1, 2, 3, 4, 5,..., 20}
E1 = {3, 6, 9, 12, 15, 18}
E2 = {4, 8, 12, 16, 20}
P(E1) = 5/20
P(not E1) = 1 - (5/20) = 15/20 = 3/4
10°
16°
40°
60°
Correct answer is D
Angle corresponding to 4 is 40/240 x 360/1 = 60°
Note that total angle in a circle is 360°.
Note also that sum of the frequencies given is 240.
In how many ways can the word MATHEMATICS be arranged?
11!/(9! 2!)
11!/(9! 2! 2!)
11!/(2! 2! 2!)
11!/(2! 2!)
Correct answer is C
Number of letter in MATHEMATICS = 11
Number of letter M = 2
Number of letter T = 2
Number of letter A = 2
Arrangement = 11!/(2! 2! 2!) ways
If the mean of the numbers 0, (x+2), (3x+6), and (4x+8) is 4, find their mean deviation.
0
2
3
4
Correct answer is C
Mean = {0 + (x+2) + (3x+6) + (4x+8)}/4 = 4
=> 0 + (x+2) + (3x+6) + (4x+8) = 16
8x + 16 = 16
x = 0
Now prepare a table showing the deviation of each of 0, (x+2), (3x+6) and (4x+8), adding the deviations will give 12.
Thus M.D = 12/4 = 3