Finding the Fourth Proportional to 1,665.87, 2,299.10 and 1,385.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,665.87 : 2,299.10 = 1,385.61 : x
2. Step 2: Convert to fraction form
   1,665.87/2,299.10 = 1,385.61/x
3. Step 3: Cross multiply
   1,665.87x = 2,299.10 × 1,385.61
4. Step 4: Simplify right side
   1,665.87x = 3,185,649.02
5. Step 5: Solve for x
   x = 3,185,649.02/1,665.87
6. Step 6: Final answer
   x = 1,912.30