Finding the Fourth Proportional to 1,387.60, 1,914.78 and 798.01

Step by Step Solution

1. Step 1: Write the proportion equation
   1,387.60 : 1,914.78 = 798.01 : x
2. Step 2: Convert to fraction form
   1,387.60/1,914.78 = 798.01/x
3. Step 3: Cross multiply
   1,387.60x = 1,914.78 × 798.01
4. Step 4: Simplify right side
   1,387.60x = 1,528,013.59
5. Step 5: Solve for x
   x = 1,528,013.59/1,387.60
6. Step 6: Final answer
   x = 1,101.19