Question
Average of 8 numbers is 70. If average of first four and
last two numbers is 80 and 45, respectively then find the fifth number given that ratio of fifth and sixth number is 4:1, respectively.Solution
Let fifth and sixth numbers be ‘4x’ and ‘x’, respectively. So, 4x + x = 70 × 8 – 80 × 4 – 45 × 2 = 150 Or, 5x = 150 Or, x = 30 So, fifth number = 30 × 4 = 120
More Average Questions
14 15 34 116 460 2325
...92,  51,  21,  13.5,  x,  4.25
find the value of (10x + x -5)?
200, 50, ‘?’, 46.875, 82.03125
20 25 54 165 662 ?
...43 36 50 29 ? 22
...25Â Â Â Â Â Â Â Â Â Â 34Â Â Â Â Â Â Â Â Â Â 61Â Â Â Â Â Â Â Â Â Â 106Â Â Â Â Â Â Â Â 169Â Â Â Â Â Â Â Â ?
...Find the wrong number in the given series.
3 1.5 1.5 ? 4.5 11.25
...2, 12, 90, 240, ?, 1260
7 13 15 29 31 57
...9 16 56 318 2424 25070
...