Finding the Fourth Proportional to 1,559.90, 2,152.67 and 861.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.90 : 2,152.67 = 861.27 : x
2. Step 2: Convert to fraction form
   1,559.90/2,152.67 = 861.27/x
3. Step 3: Cross multiply
   1,559.90x = 2,152.67 × 861.27
4. Step 4: Simplify right side
   1,559.90x = 1,854,025.78
5. Step 5: Solve for x
   x = 1,854,025.78/1,559.90
6. Step 6: Final answer
   x = 1,188.56