Finding the Fourth Proportional to 1,559.84, 2,152.52 and 861.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.84 : 2,152.52 = 861.20 : x
2. Step 2: Convert to fraction form
   1,559.84/2,152.52 = 861.20/x
3. Step 3: Cross multiply
   1,559.84x = 2,152.52 × 861.20
4. Step 4: Simplify right side
   1,559.84x = 1,853,750.22
5. Step 5: Solve for x
   x = 1,853,750.22/1,559.84
6. Step 6: Final answer
   x = 1,188.42