If $\frac{37}{13} = 2 + \frac{1}{x + \frac{1}{y + \frac{1}{z}}}$, where $x$, $y$, $z$ are natural numbers, then $x$, $y$, $z$ are
Aptitude
Simplification
Difficulty: Medium
Choose an option
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A1, 2, 5
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B1, 5, 2
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C5, 2, 11
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D11, 2, 5
Answer
Correct Answer: 1, 5, 2
Explanation
### Concept & Strategy
This problem requires converting an improper fraction into a **Continued Fraction**. The strategy is to repeatedly apply the Euclidean division algorithm: separate the integer part, and invert the remaining fractional part to find the next level's denominator.
### Step-by-Step Solution
* **Step 1: Extract the first integer part**
Divide 37 by 13. The quotient is 2, and the remainder is 11.
$$\frac{37}{13} = 2 + \frac{11}{13}$$
Comparing this to the given expression, the "2" matches. We now need to format $\frac{11}{13}$ to match $\frac{1}{x + \dots}$.
* **Step 2: Invert to find $x$**
Rewrite $\frac{11}{13}$ as $\frac{1}{\frac{13}{11}}$.
Now, extract the integer part of $\frac{13}{11}$:
$$\frac{13}{11} = 1 + \frac{2}{11}$$
By comparing this to $\frac{1}{x + \dots}$, we see that **$x = 1$**.
* **Step 3: Invert to find $y$ and $z$**
Take the remaining fraction $\frac{2}{11}$ and invert it: $\frac{1}{\frac{11}{2}}$.
Extract the integer part of $\frac{11}{2}$:
$$\frac{11}{2} = 5 + \frac{1}{2}$$
By comparing this to $y + \frac{1}{z}$, we can clearly see that **$y = 5$** and **$z = 2$**.
### Exam Strategy & Shortcut
Instead of writing out the full algebraic equations, just perform a chained division on your scratchpad.
1. $37 \div 13 = 2$ Remainder $11$.
2. Invert: $13 \div 11 = 1$ Remainder $2$. ($x=1$)
3. Invert: $11 \div 2 = 5$ Remainder $1$. ($y=5, z=2$)
The sequence of quotients and the final divisor gives you $2, 1, 5, 2$. The unknowns $x, y, z$ map directly to $1, 5, 2$.
### Common Pitfall
A common mistake is forgetting to invert the fraction at each step. Students might write $13/11$ and then incorrectly try to pull out a fraction from $11/13$ again, leading to loops or incorrect algebraic matching. Always remember the format requires $1$ in the numerator.
### Final Answer
Therefore, the correct answer is **1, 5, 2**.