Question

1. Average of five numbers is 40 out of these five average of first four
number is 35 then find the fifth number?
2. Average of seven numbers is 17 and out of these five average of first four
number is 16 then find the fifth number?
3.The average age 30 students is 15 years. If age of their teacher is included
average age is increased by 1,then find the age of the teacher?
4. The average age 19 students is 20 years if age of their teacher is included
average age is increased by 1, then find the age of the teacher?
5. average age of three brothers is 20,one of them,age is 10 years seconds
age is 20 years find the third ones age?
6. Average age of three brothers is 15,one of them,age is 15 years
seconds
age is 20 years. Find third ones age?
7. The average of five numbers is 50 of them , average of three
numbers is 40, then find the average remaining two number?
8. Average of 9 numbers is 11.if every number is multiplied by 2
then find the average of new numbers ?
9. Average of 1 Inumbers is 23.if every number is multiplied by 5
then find the average of new numbers?​

Answer 1

1.

5av.=40

total=200

4av=35

total=140

so 5th no. is= 200-140=60