The average of 11 numbers is 30.
The average of 11 numbers is 30. If the average of first six numbers is 17.5 and that of last six is 42.5, then what is the sixth number?
Answer/Solution
30
Steps/Work
Given: Average of 11 numbers = 30
Step 1: Calculate total of 11 numbers by multiplying it by average value 30 = 11 x 30 = 330
Step 2: Calculate total of first six members by multiplying it by average value 17.5 = 17.5 x 6 = 105
Step 3: Calculate total of last six members by multiplying it by average value 42.5 = 42.5 x 6 = 255
Therefore, we can find sixth number by adding value of first six and last six numbers and subtracting it from the total value of 11 numbers.
Sixth number =(105 + 255)- 330 = 30
ANSWER IS A
Step 1: Calculate total of 11 numbers by multiplying it by average value 30 = 11 x 30 = 330
Step 2: Calculate total of first six members by multiplying it by average value 17.5 = 17.5 x 6 = 105
Step 3: Calculate total of last six members by multiplying it by average value 42.5 = 42.5 x 6 = 255
Therefore, we can find sixth number by adding value of first six and last six numbers and subtracting it from the total value of 11 numbers.
Sixth number =(105 + 255)- 330 = 30
ANSWER IS A