Finding the Fourth Proportional to 1,431.96, 1,976.18 and 872.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.96 : 1,976.18 = 872.34 : x
2. Step 2: Convert to fraction form
   1,431.96/1,976.18 = 872.34/x
3. Step 3: Cross multiply
   1,431.96x = 1,976.18 × 872.34
4. Step 4: Simplify right side
   1,431.96x = 1,723,900.86
5. Step 5: Solve for x
   x = 1,723,900.86/1,431.96
6. Step 6: Final answer
   x = 1,203.88