Finding the Fourth Proportional to 1,435.29, 2,153.55 and 915.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,435.29 : 2,153.55 = 915.15 : x
2. Step 2: Convert to fraction form
   1,435.29/2,153.55 = 915.15/x
3. Step 3: Cross multiply
   1,435.29x = 2,153.55 × 915.15
4. Step 4: Simplify right side
   1,435.29x = 1,970,821.28
5. Step 5: Solve for x
   x = 1,970,821.28/1,435.29
6. Step 6: Final answer
   x = 1,373.12