Finding the Fourth Proportional to 1,026.71, 1,539.89 and 410.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,026.71 : 1,539.89 = 410.25 : x
2. Step 2: Convert to fraction form
   1,026.71/1,539.89 = 410.25/x
3. Step 3: Cross multiply
   1,026.71x = 1,539.89 × 410.25
4. Step 4: Simplify right side
   1,026.71x = 631,737.82
5. Step 5: Solve for x
   x = 631,737.82/1,026.71
6. Step 6: Final answer
   x = 615.31