Question

Here is a set of data

3.9, 2.1, 0.8, 1.5, 4.1
A= calculate the mean
B= each piece of data is increased by 5,calculate the new mean
C= each piece of new data is now double, calculate the new mean

Answer 1

A=2.48

B=7.48

C=4.96

Explanation:

A=3.9+2.1+0.8+1.5+4.1=12.4

B=

Answer 2

A = 2.48

B = 7.48

C = 14.96

Explanation:

A, the formula of Mean is similar to Average so it is, Mean = Total amount / Numbers of data :

Total = 3.9 + 2.1 + 0.8 + 1.5 + 4.1

= 12.4

Data = 5

Mean = 12.4/5

= 2.48

B, given that each data increased by 5, so you have to add 5 to all the data :

Total = (3.9+5) + (2.1+5) + (0.8+5) + (1.5+5) + (4.1+5)

= 37.4

Data = 5

Mean = 37.4/5

= 7.48

C, the new data is again doubled, so you have to multiply 2 to every data :

Total = 2(8.9) + 2(7.1) + 2(5.8) + 2(6.5) + 2(9.1)

= 74.8

Data = 5

Mean = 74.8/5

= 14.96