Difficulty: Easy
Correct Answer: 0.35
Explanation:
Introduction / Context:
This question reinforces the precedence of multiplication and division over addition with simple decimal values. It is a quick calculation if the order is respected and place values are handled correctly.
Given Data / Assumptions:
Concept / Approach:
Compute each operation separately: 0.5 * 0.5 and 0.5 ÷ 5. Then add the two results. Converting to fractions can also help: 0.5 = 1/2 and 5 = 5/1.
Step-by-Step Solution:
0.5 * 0.5 = 0.25.0.5 ÷ 5 = 0.1.Sum: 0.25 + 0.1 = 0.35.Therefore, the expression equals 0.35.
Verification / Alternative check:
Fraction form: (1/2)*(1/2) = 1/4 = 0.25, and (1/2)/5 = 1/10 = 0.1. Their sum is 7/20 = 0.35, perfectly matching the decimal result.
Why Other Options Are Wrong:
0.25 omits the division term; 0.45 adds incorrectly; 0.15 results from multiplying 0.5 and 0.5 incorrectly or dividing 0.5 by 5 wrongly.
Common Pitfalls:
Treating 0.5 ÷ 5 as 0.5/0.5; misplacing decimal points; or adding before finishing both operations of higher precedence.
Final Answer:
0.35
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