Question
The average age of a group of 8 friends is 30 years. If
one of them leaves, the average becomes 29. Find the age of the friend who left.Solution
Let the age of the person who left be ‘x’ years. So, x + (30 – 1) × 7 = 8 × 30 x + 29 × 7 = 240 x + 203 = 240 x = 240 – 203 x = 37 years So, age of the person who left was 37 years.
More Average Questions
What value should come in place of (?) in the given expression.
450 ÷ 9 + 75% of 160 − 64 ÷ 4 = ?
2/5 of 3/4 of 7/9 of 14400 = ?
7/3 of 4/5 of 15/56 of ? = 83
[564 + 32 of 18 × 9 ÷ 12 + 162 ] ÷ 4 = ?
What should come in place of (?) question mark in the given expression.
(25% of 320) + (3/8 of 400) − 30 = ?
45% of 360 - 160 + ? = √324
187 ÷ 5 ÷ 0.4 = ? – 24 × 2.4
Find the simplified value of the following expression:
[{12 + (13 × 4 ÷ 2 ÷ 2) × 5 – 8} + 13 of 8]
18 × 15 + 86 – 58 =? + 38
√(24²+285-8²-172) = ?²
