Question
In an Aerobic class, the average age of all the members
was 54.5 years, 11 members left the class and 7 new members joined. If the average age increased by 3 years and the total age decreased by 140, what was the number of members in the class initially?Solution
Let the original member be x Total age of these members = 54.5x Total age of (x – 4) members = (54.5x  – 140) years According to the question,  54.5x  – 140 = (x  – 4) `xx` 57.5 ⇒ 54.5x  – 140 = 57.5x  – 230 ⇒ 57.5x  – 54.5x  = 230 – 140 ⇒ 3x = 90  x = 30
15.99% of 549.99 ÷ 11.17 = ? ÷ 20.15
74.91% of 639.95 – 599.98% of 45 + 119.987 = ?
(4.88 × 5.76)2 - ?2 = 39.89 × 19.86
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exact value.)
- What approximate value will come in place of the question mark (?) in the following question? (Note: You are not expected to calculate the exactvalue.)
(1800.23 ÷ 29.98) + (816.32 ÷ 23.9) + 1634.11 = ?
1449.98 ÷ 50.48 × 10.12 = ? × 2.16
36.05 × 5.02 + 12.052 = ? + 9.09 × 4.04Â
(31.9)3 + (34.021)² - (16.11)3 - (42.98)² = ?