Finding the Fourth Proportional to 1,250.86, 1,876.31 and 429.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,250.86 : 1,876.31 = 429.12 : x
2. Step 2: Convert to fraction form
   1,250.86/1,876.31 = 429.12/x
3. Step 3: Cross multiply
   1,250.86x = 1,876.31 × 429.12
4. Step 4: Simplify right side
   1,250.86x = 805,162.15
5. Step 5: Solve for x
   x = 805,162.15/1,250.86
6. Step 6: Final answer
   x = 643.69