Step 1: Define the total number of jewels. Let N represent the total number of jewels. Based on the problem statement:
Jewels in box 1 = $\frac{1}{3}N$, Jewels in box 2 = $\frac{k}{5}N$, Jewels in box 3 = 66.
The total number of jewels is expressed as:
N = $\frac{1}{3}N$ + $\frac{k}{5}N$ + 66.
Step 2: Simplify the equation. Rearrange the terms:
N − $\frac{1}{3}N$ − $\frac{k}{5}N$ = 66.
Combine like terms:
$\left( 1 - \frac{1}{3} - \frac{k}{5} \right)N$ = 66.
Simplify the coefficients:
$\left( \frac{3}{3} - \frac{1}{3} - \frac{k}{5} \right)N$ = 66 = =\(>\) $\left( \frac{2}{3} - \frac{k}{5} \right)N$ = 66.
Step 3: Solve for k. Given that k is a positive integer, test values such that $\frac{2}{3} - \frac{k}{5}<0$. Let k = 2:
$\frac{2}{3} - \frac{2}{5} = \frac{10}{15} - \frac{6}{15} = \frac{4}{15}$
Substitute this value into the equation:
$\frac{4}{15}N$ = 66 = =\(>\) N = $\frac{66 \times 15}{4}$ = 990 jewels.
Answer: 990