Finding the Fourth Proportional to 871.89, 1,201.30 and 801.15

Step by Step Solution

1. Step 1: Write the proportion equation
   871.89 : 1,201.30 = 801.15 : x
2. Step 2: Convert to fraction form
   871.89/1,201.30 = 801.15/x
3. Step 3: Cross multiply
   871.89x = 1,201.30 × 801.15
4. Step 4: Simplify right side
   871.89x = 962,421.50
5. Step 5: Solve for x
   x = 962,421.50/871.89
6. Step 6: Final answer
   x = 1,103.83