Finding the Fourth Proportional to 1,387.67, 1,915.39 and 798.33

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.67 : 1,915.39 = 798.33 : x
2. Step 2: Convert to fraction form
   1,387.67/1,915.39 = 798.33/x
3. Step 3: Cross multiply
   1,387.67x = 1,915.39 × 798.33
4. Step 4: Simplify right side
   1,387.67x = 1,529,113.30
5. Step 5: Solve for x
   x = 1,529,113.30/1,387.67
6. Step 6: Final answer
   x = 1,101.93