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.
If 4x+2y=16 and 6x-2y=4 , find the value of (y-x).
8
2
4
6
Correct answer is B
Using elimination method:
4x+2y=16 * 6 --> 24x +12y=96 ... eqn iii
6x-2y=4 * 4 --> 24x - 8y = 16 ... eqn iv
Subtract eqn iv from iii
20y = 80
y = 4
Subst. y for 4 in 4x + 2y = 16
--> 4x + 2(4) = 16
--> 4x = 16 - 8
--> 4x = 8
--> x = 2
: The value of (y-x) is 4 - 2 = 2
\(\frac{√21}{21}\)
7\(\frac{√21}{21}\)
\(\frac{√21}{3}\)
3√21
Correct answer is C
2√7- 14/√7 +7/√21
L.C.M is √21
\(\frac{√21 * 2√7 - √3 *14 + 7}{√21}\)
=\(\frac{2 * 7√3 - 14√3 + 7}{√21}\)
= \(\frac{14√3 - 14√3 + 7}{√21}\)
=\(\frac{7}{√21}\)
or
\(\frac{7 \times √21}{√21 \times √21}\)
= \(\frac{7 \times √21}{21}\) or \(\frac{√21}{3}\)
5km
6km
7km
3km
Correct answer is A
Circumference of the circular track = 9km
Distance covered = 302km
Number of complete circles or revolutions from the starting point = 302/9 =33 circles and additional 5km.
So, the distance of the cyclist from the starting point would be 5km
If 16 * 2\(^{(x + 1)}\) = 4\(^x\) * 8\(^{(1 - x)}\), find the value of x.
-4
4
1
-1
Correct answer is D
16 * 2\(^{(x + 1)}\) = 4\(^x\) * 8\(^{(1 - x)}\)
= 2\(^4\) * 2\(^{(x + 1)}\) = 2\(^{2x}\) * 2\(^{3(1 - x)}\)
--> 4 + x + 1 = 2x + 3 - 3x
collect like terms
--> x - 2x + 3x = 3 - 1 - 4
--> 2x = -2
--> x = -1
3 years
10 years
5 years
15 years
Correct answer is C
Mensah’s age is 5. Thus,
Joyce’s age is 15 (5*3=15)
The difference between their ages is 10 (15–5=10)
As we ought to find how many years Joyce’s age will be twice of Mensah’s age, we should write down the following :
15+X=2*(5+X)
15+X=10+2X lets add (-10-X) to both sides of the equation and
15+X-10-X = 10+2X-10-X
5=X —-> X=5
After 5 years Joyce’s age will be 20 (15+5=20)
After 5 years Mensah’s age will be 10 (5+5=10)
After 5 years Joyce will be twice as old as Mensah (10*2=20)