Question

Mean of 5 numbers is 18. If one more num-
ber is added

into group, the new mean is
20. Then the new number added is
1) 30
2) 203) 25
4) 15
is​

Answer 1

Answer:

30

Explanation:

let sum of 5 numbers be m.

then

Mean = m/5 = 18

therefore, m=18*5=90

let the new number be added be x.

then, new mean = (m+x)/6=20

m+x=20*6

m+x=120

90+x=120 (since m = 90)

x= 120-90

x=30

Therefore, the new number added is 30.