Difficulty: Easy
Correct Answer: 5
Explanation:
Introduction:
This question introduces a custom operator "#" applied to ordered pairs of numbers. Instead of its usual use as a symbol in programming or text, it represents a simple hidden arithmetic operation. We are given three examples and asked to determine the value of 8 # 40 under the same rule. This is a direct test of pattern recognition in numerical reasoning.
Given Data / Assumptions:
The provided relationships are:
1) 6 # 30 = 5
2) 8 # 24 = 3
3) 7 # 28 = 4
We need 8 # 40. We assume:
1) The operation # is the same in all four cases.
2) The rule likely involves a straightforward combination, such as division, between the second and first numbers.
Concept / Approach:
Looking at each pair, the results 5, 3, and 4 are small compared with the second numbers 30, 24, and 28. A good first guess is that the result might be obtained by dividing the second number by the first. If this hypothesis works consistently for all given examples, we will then apply it to the new pair 8 and 40.
Step-by-Step Solution:
Step 1: For 6 # 30, compute 30 / 6. The result is 5, matching the given answer.Step 2: For 8 # 24, compute 24 / 8. The result is 3, again matching the given value.Step 3: For 7 # 28, compute 28 / 7. The result is 4, which also matches the given output.Step 4: Since in each example the result is the second number divided by the first number, we define a # b = b / a.Step 5: Apply this rule to 8 # 40. Here a = 8 and b = 40.Step 6: Compute 40 / 8 = 5.Step 7: Therefore, the value of 8 # 40 is 5.
Verification / Alternative check:
We can double check that no alternative simple pattern is needed. For example, if we tried a / b instead, we would obtain fractions less than 1, clearly not matching the given integer outputs. Products and sums give much larger numbers, so they are unsuitable. The division b / a is the only natural and consistent explanation for all three examples.
Why Other Options Are Wrong:
The value 47 or 24 or 6 cannot be generated by simply dividing the second number by the first for any of the examples. The value 4 would be correct for 7 # 28, but not for 8 # 40. Thus, the only option that matches the pattern consistently for the new pair is 5.
Common Pitfalls:
One common mistake is to test only the first example and prematurely conclude a rule, such as subtracting or adding a constant, without checking the other two examples. Another pitfall is accidentally reversing the order of division and computing a / b instead of b / a. Always verify your rule on every example provided before using it on the unknown case.
Final Answer:
Under the given pattern, the value of 8 # 40 is 5.
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