$15:4::21:6:: 42:?$
Number Analogy Problem Breakdown
The question presents a number analogy problem. We need to identify the relationship between the first number and the second number in the first pair (15:4) and apply the same relationship to the third number (42) to find the missing fourth number.
Identifying the Pattern
Let's examine the given pairs:
- Pair 1: 15 is related to 4
- Pair 2: 21 is related to 6
We look for a consistent mathematical operation or rule connecting the numbers in each pair.
Consider the rule: First Number = (Second Number $\times$ 3) + 3
Let's test this rule:
- For 15:4: Does $15 = (4 \times 3) + 3$? Yes, $15 = 12 + 3$.
- For 21:6: Does $21 = (6 \times 3) + 3$? Yes, $21 = 18 + 3$.
The pattern holds true for both pairs.
Calculating the Missing Number
Now, we apply the same pattern to the third pair (42 : ?), where '?' represents the missing number.
Let the missing number be represented by $x$. Using the identified pattern:
First Number = (Second Number $\times$ 3) + 3
Substituting the values:
$42 = (x \times 3) + 3$
Now, solve for $x$:
- Subtract 3 from both sides:
$42 - 3 = x \times 3$
$39 = 3x$ - Divide both sides by 3:
$x = \frac{39}{3}$
$x = 13$
Therefore, the missing number is 13.
Final Answer Check
The calculated missing number is 13, which corresponds to Option C.
Important Questions from Reasoning Analogy
WSO is related to XXUP in a certain way based on the English alphabetical order. In the same way, ONKG is related to PPMH. To which of the following is VURN related, following the same logic?
Select the word-pair that best represents a similar relationship to the one expressed in the pair of words given below.
(The words must be considered as meaningful English words and must not be related to each other based on the number of letters/number of consonants/vowels in the word.)
Withdraw : ExtractSelect the word-pair that best represents a similar relationship to the one expressed in the pair of words given below.
Duleep Trophy : Cricket
Select the set in which the numbers are related in the same way as are the numbers of the following sets.
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g., 13 – Operations on 13 such as adding/subtracting/multiplying etc. to 13, can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
(4, 35, 11)
(1, 82, 61)
7 is related to 30 following a certain logic. Following the same logic, 14 is related to 100. To which of the following is 22 related following the same logic?
(NOTE: Operations should be performed on the whole numbers, without breaking down the numbers into their constituent digits. E.g., 13 – Operations on 13 such as adding/subtracting/multiplying etc. to 13 can be performed. Breaking down 13 into 1 and 3 and then performing mathematical operations on 1 and 3 is not allowed.)
