Question

The daily expenses of 40 families has been shown by the following frequency distribution:

Expenses (in ₹)	500 – 700	700 – 900	900 – 1100	1100 – 1300	1300 – 1500
Number of families	6	8	10	9	7

Find the mean daily expenses.

Answer 1

1. Frequency distribution table

Expenses (in ₹)	Frequency (fi)	Class Mark  `bb(((x_i = "Lower" + "Upper")/2)`	fi × xi
500 – 700	6	600	3,600
700 – 900	8	800	6,400
900 – 1100	10	1,000	10,000
1100 – 1300	9	1,200	10,800
1300 – 1500	7	1,400	9,800
Total	Σfi = 40		Σfixi = 40,600

2. Apply the mean formula

`barx = (40,600)/40`

`barx = 1,015`