Finding the Fourth Proportional to 2,572.72, 3,859.62 and 842.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,572.72 : 3,859.62 = 842.56 : x
2. Step 2: Convert to fraction form
   2,572.72/3,859.62 = 842.56/x
3. Step 3: Cross multiply
   2,572.72x = 3,859.62 × 842.56
4. Step 4: Simplify right side
   2,572.72x = 3,251,961.43
5. Step 5: Solve for x
   x = 3,251,961.43/2,572.72
6. Step 6: Final answer
   x = 1,264.02