Finding the Fourth Proportional to 1,665.62, 2,499.06 and 691.64

Step by Step Solution

1. Step 1: Write the proportion equation
   1,665.62 : 2,499.06 = 691.64 : x
2. Step 2: Convert to fraction form
   1,665.62/2,499.06 = 691.64/x
3. Step 3: Cross multiply
   1,665.62x = 2,499.06 × 691.64
4. Step 4: Simplify right side
   1,665.62x = 1,728,449.86
5. Step 5: Solve for x
   x = 1,728,449.86/1,665.62
6. Step 6: Final answer
   x = 1,037.72