Finding the Fourth Proportional to 1,399.31, 2,101.73 and 880.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.31 : 2,101.73 = 880.23 : x
2. Step 2: Convert to fraction form
   1,399.31/2,101.73 = 880.23/x
3. Step 3: Cross multiply
   1,399.31x = 2,101.73 × 880.23
4. Step 4: Simplify right side
   1,399.31x = 1,850,001.40
5. Step 5: Solve for x
   x = 1,850,001.40/1,399.31
6. Step 6: Final answer
   x = 1,322.09