Question

9. The average of 11 numbers is 10.9. If the average of first six is 10.5 and that of the last six is 11.4 the sixth number is? (a) 11 (b) 11.3 (c) 11.4 (d) 11.5​

Answer 1

Answer:

the answer is option no d 11. 5

Step-by-step explanation:

the average of 11 nos is 10.9 given which means that their sum is 119.9

the average of first 6 nos is 10.5 which means their sum is 63

now subtract 63 from 119.9 , u get 56.9 ,which when divided by 5 would give the average of the next five numbers

but we see that there is a sixth no which when added to 56.9 and divided by 6 gives 11.4 which means the sum of the 5 nos and the sixth one is  68.4

then i just subtracted 56.9 from 68.4 and got the value