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
- What will come in place of (?), in the given expression.
(12% of 250) + (30% of 400) = ? What will come in place of (?) question mark in the following expression.
5(1/4) + 3(1/2) - 2(1/8) = ?
(-251 × 21 × -12) ÷ ? = 158.13
1555.5 + 1000.8 – 1354.3 = ? + 52
135.37 – 50.24 + 629.09 – 199.50 = ? – 214.68 + 42.65
What value should come in place of (?) question mark in the given expression.
75% of 320 + 40% of 150 = ?
? = 2640 ÷ {(35% of 1240) – 170}Â
Simplify the expression:
(9x² - 25) / (3x + 5)
What will come in the place of question mark (?) in the given expression?
? = 90% of 25% of (40 × 200) + 300
