Finding the Fourth Proportional to 1,515.90, 2,270.55 and 929.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,515.90 : 2,270.55 = 929.15 : x
2. Step 2: Convert to fraction form
   1,515.90/2,270.55 = 929.15/x
3. Step 3: Cross multiply
   1,515.90x = 2,270.55 × 929.15
4. Step 4: Simplify right side
   1,515.90x = 2,109,689.53
5. Step 5: Solve for x
   x = 2,109,689.53/1,515.90
6. Step 6: Final answer
   x = 1,391.71