Finding the Fourth Proportional to 983.18, 1,475.76 and 872.72

Step by Step Solution

1. Step 1: Write the proportion equation
   983.18 : 1,475.76 = 872.72 : x
2. Step 2: Convert to fraction form
   983.18/1,475.76 = 872.72/x
3. Step 3: Cross multiply
   983.18x = 1,475.76 × 872.72
4. Step 4: Simplify right side
   983.18x = 1,287,925.27
5. Step 5: Solve for x
   x = 1,287,925.27/983.18
6. Step 6: Final answer
   x = 1,309.96