Quantitative Aptitude
ALLIGATION MCQs
Let the total number of girls and boys be G and B respectively.
Given,
Pass percentage of girls = 70%
Pass percentage of boys = 65%
Total pass percentage = 67%
We can write,
\frac{70}{100}G + \frac{65}{100}B = \frac{67}{100}(G+B)
\therefore \frac{35}{100}G + \frac{65}{100}B = \frac{33}{100}(G+B)
On solving the equation, we get,
B = \frac{35}{32}G
Now,
G + B = 750
On substituting the value of B in the above equation, we get,
G + \frac{35}{32}G = 750
On solving the equation, we get
G = 400
Hence, the number of boys that appeared in the examination = B = \frac{35}{32}G = \frac{35}{32} \times 400 = 450
If you think the solution is wrong then please provide your own solution below in the comments section .
Average monthly salary of labourers and supervisors = Rs 1250
Average monthly salary of supervisors = Rs 2450
Average monthly salary of labourers = Rs 950
Let the number of labourers be 'x' and the number of supervisors be 'y'
Therefore,
Average monthly salary of labourers and supervisors = (950x + 2450y)/(x + y)
On rearranging, we get
950x + 2450y = 1250 (x + y)
Simplifying further, we get
850x = -1200y
Divide both sides by 850
x = -1400/850 y
Since y = 6
Therefore, x = -1400/850 x 6
x = 24
Hence, the number of labourers = 24.
If you think the solution is wrong then please provide your own solution below in the comments section .