Question

Average pocket allowance of 6 students is ₹45. Of these, pocket allowance of 5 students is 20, 30, 22, 24 and 32 respectively. What is the pocket allowance of the sixth student?

Answer 1

Given:
Average, $\overline{X}$ = 45
Number of students, N = 6

Let sixth student's allowance be Z

Substituting the given values in the formula for mean
$$\begin{gathered} \overline{X}=\frac{\Sigma X}{N} \\ 45=\frac{20+30+22+24+32+Z}{6} \end{gathered}$$
or, 45 × 6 = 128 + Z
or, 270 − 128 = Z
or, Z = 142
Hence, sixth student's allowance is Rs. 142