Finding the Fourth Proportional to 1,002.78, 1,502.15 and 591.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,002.78 : 1,502.15 = 591.71 : x
2. Step 2: Convert to fraction form
   1,002.78/1,502.15 = 591.71/x
3. Step 3: Cross multiply
   1,002.78x = 1,502.15 × 591.71
4. Step 4: Simplify right side
   1,002.78x = 888,826.71
5. Step 5: Solve for x
   x = 888,826.71/1,002.78
6. Step 6: Final answer
   x = 886.36