Solve for the missing factor in a percent equation: Find ? in 45 × ? = 25% of 900.
Aptitude
Percentage
Difficulty: Easy
Choose an option
Answer
Correct Answer: 5
Explanation
Introduction / Context:This is a direct application of percentages and basic algebra. We equate a product to a percentage of a known number and solve for the unknown factor.
Given Data / Assumptions:
- Equation: 45 * ? = 25% of 900.
- 25% = 0.25.
Concept / Approach:First evaluate the right-hand side (RHS). Then divide by 45 to find the unknown.
Step-by-Step Solution:
Compute RHS: 25% of 900 = 0.25 * 900 = 225.So 45 * ? = 225.? = 225 / 45 = 5.Verification / Alternative check:Check: 45 * 5 = 225, which equals 25% of 900. The equation balances.
Why Other Options Are Wrong:
- 16.20 and 2.5 arise from arithmetic slips (e.g., dividing by 9 or 18 incorrectly).
- 4 gives 180 on the left, not 225.
- 500 is wildly off; it confuses percent with multiplication by 100.
Common Pitfalls:Miscomputing 25% of 900; remember that 25% is one-fourth, and 900/4 = 225.
Final Answer:5