Finding the Fourth Proportional to 1,431.86, 1,976.01 and 872.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.86 : 1,976.01 = 872.51 : x
2. Step 2: Convert to fraction form
   1,431.86/1,976.01 = 872.51/x
3. Step 3: Cross multiply
   1,431.86x = 1,976.01 × 872.51
4. Step 4: Simplify right side
   1,431.86x = 1,724,088.49
5. Step 5: Solve for x
   x = 1,724,088.49/1,431.86
6. Step 6: Final answer
   x = 1,204.09