Select the number pair in which the two numbers are related in the same way as are the two numbers of the following number-pair.
12 : 3
In this question, we are given a pair of numbers, 27 and 8, and we need to find another pair from the given options that shares the same relationship. This type of problem tests our ability to identify patterns and logical connections between numbers.
Let's examine the relationship between the two numbers, 27 and 8. We need to think about various mathematical operations or patterns that could connect 27 and 8. Some possibilities include:
Let's try to find a simple relationship. If we divide the first number, 27, by a small integer, say 3, we get 9. How can we get 8 from 9? By subtracting 1. So, let's test the relationship:
Second Number = (First Number / 3) - 1
Let's apply this to the given pair 27 : 8:
\( (27 \div 3) - 1 = 9 - 1 = 8 \)
This relationship holds true for the given number pair 27 : 8.
Now, we will apply this identified relationship to each of the given options to see which pair satisfies the same rule: Second Number = (First Number / 3) - 1.
Option 1: 12 : 3
Let's apply the relationship to the first number, 12:
\( (12 \div 3) - 1 = 4 - 1 = 3 \)
The result is 3, which is the second number in the pair 12 : 3. This option fits the relationship.
Option 2: 39 : 14
Let's apply the relationship to the first number, 39:
\( (39 \div 3) - 1 = 13 - 1 = 12 \)
The result is 12, which is not equal to the second number in the pair (14). This option does not fit the relationship.
Option 3: 19 : 5
Let's apply the relationship to the first number, 19:
The first number, 19, is not divisible by 3. So, this option cannot fit the relationship (First Number / 3) - 1, which requires the first number to be divisible by 3.
Option 4: 33 : 9
Let's apply the relationship to the first number, 33:
\( (33 \div 3) - 1 = 11 - 1 = 10 \)
The result is 10, which is not equal to the second number in the pair (9). This option does not fit the relationship.
Based on our analysis, only Option 1 (12 : 3) follows the same relationship as the given pair 27 : 8.
The relationship is: The second number is obtained by dividing the first number by 3 and then subtracting 1.
| Number Pair | Apply Relationship \( (N \div 3) - 1 \) | Result | Matches Second Number? |
|---|---|---|---|
| 27 : 8 | \( (27 \div 3) - 1 \) | \( 9 - 1 = 8 \) | Yes |
| 12 : 3 (Option 1) | \( (12 \div 3) - 1 \) | \( 4 - 1 = 3 \) | Yes |
| 39 : 14 (Option 2) | \( (39 \div 3) - 1 \) | \( 13 - 1 = 12 \) | No (Expected 14) |
| 19 : 5 (Option 3) | 19 is not divisible by 3 | - | No |
| 33 : 9 (Option 4) | \( (33 \div 3) - 1 \) | \( 11 - 1 = 10 \) | No (Expected 9) |
Therefore, the number pair that is related in the same way as 27 : 8 is 12 : 3.
Understanding number analogies involves recognizing various types of relationships. Here's a quick revision:
| Relationship Type | Description | Example |
|---|---|---|
| Arithmetic Operations | Adding, subtracting, multiplying, or dividing the first number (or its digits) to get the second. | 5 : 10 (Multiply by 2) 10 : 8 (Subtract 2) 15 : 5 (Divide by 3) |
| Powers/Roots | Relationship based on squares, cubes, square roots, cube roots. | 4 : 16 (Square) 27 : 3 (Cube root) 8 : 64 (Cube of base minus 1, then square) |
| Digit Based | Operations on the digits of the first number (sum, product, difference) to get the second number. | 23 : 5 (Sum of digits) 12 : 2 (Product of digits) 41 : 3 (Difference of digits) |
| Combinations | Applying a sequence of operations. | 10 : 21 (Multiply by 2, add 1) 25 : 55 (Multiply by 2, add 5) 27 : 8 (Divide by 3, subtract 1) |
| Prime/Composite Numbers | Relationship based on whether numbers are prime or composite. | 7 : 11 (Next prime number) |
When approaching number analogy problems like 27 : 8, it's helpful to follow a systematic approach:
Practicing with various types of number analogies helps in quickly recognizing patterns during exams.
Select the option in which the numbers are related in the same way as are the numbers of the following set.
(4, 8, 16)
Select the option that is related to the third number in the same way as the second number is related to the first number.
23 : 441 : : 28 : ?
Select the option that is related to the third number in the same way as the second number is related to the first number and the sixth number is related to the fifth number.
12 : 72 ∷ 18 : ? ∷22 : 242Select the option that is related to the third number in the same way as the second number is related to the first number.
7 : 56 :: 11 : ?
Select the option in which the numbers are related in the same way as are the numbers of the following set.
(12, 60, 84)