Finding the Fourth Proportional to 1,061.31, 1,588.87 and 788.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,061.31 : 1,588.87 = 788.61 : x
2. Step 2: Convert to fraction form
   1,061.31/1,588.87 = 788.61/x
3. Step 3: Cross multiply
   1,061.31x = 1,588.87 × 788.61
4. Step 4: Simplify right side
   1,061.31x = 1,252,998.77
5. Step 5: Solve for x
   x = 1,252,998.77/1,061.31
6. Step 6: Final answer
   x = 1,180.62