Question

The following table shows the electricity (in units) used by 25 families of Eklara village in a month of May. Complete the table and answer the following questions.

Electricity used (Units) xi	No. of families (frequency) fi	fi × xi
30	7	_
45	2	_
60	8	_
75	5	_
90	3	_
	N =_	\(\sum f_i \times x_i =\) _

i. How many families use 45 units electricity? 

ii. State the score, the frequency of which is 5. 

iii. Find N, and \(\sum f_i \times x_i =\) . 

iv. Find the mean of electricity used by each family in the month of May.

Answer 1

Electricity used (Units) xi	No. of families (frequency) fi	fi × xi
30	7	210
45	2	90
60	8	480
75	5	375
90	3	270
	N = 25	\(\sum f_i \times x_i =\) 1425

i. 2 families used 45 units of electricity. 

ii. The score for which the frequency is 5 is 75.

iii. N = 25 and \(\sum f_i \times x_i =\) 1425

iv.

 

The mean of electricity used by each.