Finding the Fourth Proportional to 1,399.05, 2,098.56 and 915.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.05 : 2,098.56 = 915.18 : x
2. Step 2: Convert to fraction form
   1,399.05/2,098.56 = 915.18/x
3. Step 3: Cross multiply
   1,399.05x = 2,098.56 × 915.18
4. Step 4: Simplify right side
   1,399.05x = 1,920,560.14
5. Step 5: Solve for x
   x = 1,920,560.14/1,399.05
6. Step 6: Final answer
   x = 1,372.76