Question

If there are 30 numbers and the average of the first 10 numbers is equal to the average of last 20 number what is the sum of last 20 numbers
a) same as the sum of first 10 numbers
b) 2 times the sum of first 10 numbers
c) average of first 10 numbers
d) none of the above; If there are 30 numbers and the average of the first 10 numbers is equal to the average of last 20 number what is the sum of last 20 numbers; a) same as the sum of first 10 numbers; b) 2 times the sum of first 10 numbers; c) average of first 10 numbers; d) none of the above

Answer 1

Answer: 2 times average of first 10 numbers

Step-by-step explanation:

Average of first 10 numbers = average if last 20 numbers

Sum of 10 numbers = Average * 10

Sum of 20 numbers/sum of 10 numbers = 20* average / 10 * average

=2

So average of last 20 numbers is twice the average of first 10 numbers