Finding the Fourth Proportional to 1,355.52, 1,871.32 and 915.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.52 : 1,871.32 = 915.74 : x
2. Step 2: Convert to fraction form
   1,355.52/1,871.32 = 915.74/x
3. Step 3: Cross multiply
   1,355.52x = 1,871.32 × 915.74
4. Step 4: Simplify right side
   1,355.52x = 1,713,642.58
5. Step 5: Solve for x
   x = 1,713,642.58/1,355.52
6. Step 6: Final answer
   x = 1,264.20