Finding the Fourth Proportional to 1,661.43, 2,292.72 and 915.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,661.43 : 2,292.72 = 915.39 : x
2. Step 2: Convert to fraction form
   1,661.43/2,292.72 = 915.39/x
3. Step 3: Cross multiply
   1,661.43x = 2,292.72 × 915.39
4. Step 4: Simplify right side
   1,661.43x = 2,098,732.96
5. Step 5: Solve for x
   x = 2,098,732.96/1,661.43
6. Step 6: Final answer
   x = 1,263.21