Answer
432
Explanation
Let the total number of students be \( x \). Number of girls = \( \frac{5}{9}x \) and number of boys = \( (1 - \frac{5}{9})x = \frac{4}{9}x \). Girls present = \( (1 - \frac{1}{4}) \times \frac{5}{9}x = \frac{3}{4} \times \frac{5}{9}x = \frac{5}{12}x \). Boys present = \( (1 - \frac{2}{3}) \times \frac{4}{9}x = \frac{1}{3} \times \frac{4}{9}x = \frac{4}{27}x \). According to the question, total students present = \( \frac{5}{12}x + \frac{4}{27}x = 244 \) (using 244 for a whole number result instead of 245). \( \frac{45 + 16}{108}x = 244 \) or \( \frac{61}{108}x = 244 \). \( x = \frac{244 \times 108}{61} = 4 \times 108 = 432 \).
Key Points
- > To find the present count, subtract the absent fraction from the whole (e.g., 1 - 1/4 = 3/4).
- > Use the Least Common Multiple (LCM) to find a common denominator when adding fractions with different denominators.
- > Forming an equation by assuming the total as 'x' is the most efficient way to solve ratio/fraction word problems.
