Finding the Fourth Proportional to 1,387.83, 1,915.25 and 945.93

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.83 : 1,915.25 = 945.93 : x
2. Step 2: Convert to fraction form
   1,387.83/1,915.25 = 945.93/x
3. Step 3: Cross multiply
   1,387.83x = 1,915.25 × 945.93
4. Step 4: Simplify right side
   1,387.83x = 1,811,687.70
5. Step 5: Solve for x
   x = 1,811,687.70/1,387.83
6. Step 6: Final answer
   x = 1,305.41