Finding the Fourth Proportional to 1,387.56, 1,914.89 and 798.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.56 : 1,914.89 = 798.09 : x
2. Step 2: Convert to fraction form
   1,387.56/1,914.89 = 798.09/x
3. Step 3: Cross multiply
   1,387.56x = 1,914.89 × 798.09
4. Step 4: Simplify right side
   1,387.56x = 1,528,259.75
5. Step 5: Solve for x
   x = 1,528,259.75/1,387.56
6. Step 6: Final answer
   x = 1,101.40