Difficulty: Easy
Correct Answer: 21
Explanation:
Introduction / Context:
This is a number analogy based on operations with the digits of a two digit number. You are given 41 : 4 and must find which number should be associated with 37 in the same way. Many such questions revolve around sums or products of the digits. Here, the pattern turns out to be based on the product of the two digits in each number.
Given Data / Assumptions:
Concept / Approach:
We first check whether the related number could be the sum of the digits or their product. For 41, the sum of the digits is 4 + 1 = 5, which does not match 4, but the product is 4 * 1 = 4, which matches perfectly. So the pattern in the example pair is that the second number is the product of the digits of the first. We can then apply this to 37, where the digits are 3 and 7, and see which option matches the resulting product.
Step-by-Step Solution:
Step 1: Take the number 41 from the example pair.
Step 2: Separate its digits: 4 and 1.
Step 3: Compute their product: 4 * 1 = 4, which matches the related number given on the right side of the pair.
Step 4: Conclude that the rule is: result = (tens digit) * (units digit).
Step 5: Now apply this rule to 37. Its digits are 3 and 7.
Step 6: Multiply these digits: 3 * 7 = 21.
Step 7: Compare this result with the options. 21 appears as option b, so that must be the correct answer.
Verification / Alternative check:
Test quickly whether the sum based rule would work. For 41, 4 + 1 = 5, which does not match 4, so sum is not correct. Also, there is no obvious square or cube relation: 41 squared is 1681, which is not 4. The digit product rule is the only simple pattern that precisely explains 41 : 4 and produces a value that matches one of the options for 37. As a quick further check, 37 has digits whose sum is 10 but whose product is 21; only 21 is present in the answer set, reinforcing the correctness of the digit product pattern.
Why Other Options Are Wrong:
The numbers 34, 22, and 16 cannot be obtained by multiplying the digits 3 and 7. Using any of them would require a different rule than the one that connects 41 to 4. For example, 16 would be 4 squared, but there is no comparable square relationship for 37 that remains consistent with 41 : 4. Therefore, these alternatives break the analogy and must be rejected.
Common Pitfalls:
A common error is to look for operations directly on the two digit number, such as dividing it by a constant or subtracting a fixed amount, rather than looking at the digits. Another pitfall is to miscalculate the product of the digits under time pressure. Remember that in many two digit analogies, the simplest patterns involve digit sums or products, so always check those first before moving to more complicated ideas.
Final Answer:
Following the pattern that the related number is the product of the digits, 41 gives 4 and 37 gives 21, so the correct answer is 21.
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