# An analysis of monthly wages paid to workers in two firms A and B, belonging to the same industry, gives the following results:

Firm A Firm B

No. of Wage Earners 586 648

Mean of Monthly Wages Rs. 5253 Rs. 5253

Variance of distribution of wages 100 121

(i) Which firm A or B pays larger amount as monthly wages?

(ii) Which firm, A or B, shows greater variability in individual wages?

**Solution:**

(i) Monthly wages of firm A = Rs 5253

Number of wage earners in firm A = 586

Therefore,

The total amount paid is Rs. 5253 × 586

Monthly wages of firm B = Rs 5253

Number of wage earners in firm B= 648

⇒ Total amount paid = Rs. 5253 × 648

Thus,

firm B pays the larger amount as monthly wages as the number of wage earners in firm B are more than the number of wage earners in firm A.

(ii) Variance of the distribution of wages in firm A (σ_{12})

= 100

⇒ Standard deviation of the distribution of wages in firm A(σ_{1})

= √100 = 10

⇒Variance of the distribution of wages in firm B (σ_{1}²)

= 121

⇒ Standard deviation of the distribution of wages in firm A(σ_{1})

= √121 = 11

The mean of monthly wages of both the firms is same.

Therefore, the firm with greater standard deviation will have more variability.

Thus, firm B has greater variability in the individual wages

NCERT Solutions Class 11 Maths Chapter 15 Exercise 15.3 Question 3

## An analysis of monthly wages paid to workers in two firms A and B, belonging to the same industry, gives the following results: (i) Which firm A or B pays larger amount as monthly wages? (ii) Which firm, A or B, shows greater variability in individual wages?

**Solution:**

From the given data, (i) Firm B pays the larger amount as monthly wages (ii) Firm B has greater variability in the individual wages