Question
In a school with 400 students, the average of the age of
the boys is 16 years and that of the girls is 12 years. If the average age of the school is 14 years 9 months. Then the number of girls in the school is.Solution
Let the number of Boys be ‘x’ Sum of ages of boys = x x 16 Sum of ages of girls = (400 - x ) x 12 According to question, x × 16 + (400 - x) × 12 = 400 × `14 (3/4)` 16x + 4800 - 12x = 400 × `59/4` 4x + 4800 = 5900 4x = 1100 x = 275 Number of girls = 400 - 275 = 125
What will come in the place of question mark (?) in the given expression?
(63 - ?) ÷ 5 + √625 = 19 X (9 - 6)
- What will come in place of (?), in the given expression.
(4² + 6²) × 2 = ? What will come in the place of question mark (?) in the given expression?
(40/25) X 80 - ? = 45% of 300 - 5525.6% of 250 + √? = 119
1220 ÷ 61 ÷ 5 + 450 of 20% - 70 = √ ?
Simplify the expression:
(5x + 15) / (x² + 3x)
What will come in the place of question mark (?) in the given expression?Â
435 ÷ 29 X 792 ÷ 44 = √(? + 14) + 35 + 221 ÷ 17
...192.251 + 326.233 + 125.021 + 19.273 = ?
36% of 640 – 12.5% of 352 + 25% of 640 = ? – 48% of 432
Simplify the following expressions and choose the correct option.
18 * 15 - {3/5 of 250 + 72}
