If 8 # 2 @ 5 = 21 and 4 # 6 @ 2 = 26, then what will be 3 # 7 @ 9?
30
This question asks us to find a hidden mathematical rule that connects the numbers and the symbols '#' and '@' based on the examples provided. Once we figure out the rule, we can apply it to the new set of numbers to find the result.
We are given two examples:
We need to determine what operations the symbols '#' and '@' represent. Let's assume the standard order of operations might apply, or perhaps the symbols represent operations performed in sequence from left to right.
Let's try different combinations of basic arithmetic operations for the symbols '#' and '@'. Common operations include addition (+), subtraction (-), multiplication ($\times$), and division ($\div$).
Let's consider the first example: 8 # 2 @ 5 = 21.
The combination of multiplication for '#' and addition for '@' worked for the first example: $\left(\text{First Number } \# \text{ Second Number}\right) \ @ \ \text{Third Number} = \left(\text{First Number} \times \text{ Second Number}\right) + \text{Third Number}$.
Let's test this potential rule with the second example: 4 # 6 @ 2 = 26.
Using the rule: $\left(4 \times 6\right) + 2 = 24 + 2 = 26$.
This also matches the second example.
So, the pattern is confirmed: The operation '$#$' represents multiplication ($\times$), and the operation '$@$' represents addition (+).
Now we apply the discovered rule to the expression 3 # 7 @ 9.
According to our rule:
The expression becomes $\left(3 \times 7\right) + 9$.
Let's perform the calculation following the standard order of operations (perform multiplication before addition):
First, calculate $3 \times 7$:
$\left(3 \times 7\right) + 9 = 21 + 9$
Next, perform the addition:
$21 + 9 = 30$
Based on the pattern found in the given examples, the value of 3 # 7 @ 9 is 30.
| Expression | Rule Application ($\# = \times, \ @ = +$) | Calculation | Result |
|---|---|---|---|
| 8 # 2 @ 5 | $(8 \times 2) + 5$ | $16 + 5$ | 21 |
| 4 # 6 @ 2 | $(4 \times 6) + 2$ | $24 + 2$ | 26 |
| 3 # 7 @ 9 | $(3 \times 7) + 9$ | $21 + 9$ | 30 |
Logic puzzles often involve finding patterns or rules based on given examples. Here are some common techniques used to solve such problems:
A systematic approach, trying simple possibilities first and then moving to more complex ones, is often helpful in cracking these types of logic puzzles.
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