Finding the Fourth Proportional to 1,559.61, 2,152.29 and 860.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.61 : 2,152.29 = 860.99 : x
2. Step 2: Convert to fraction form
   1,559.61/2,152.29 = 860.99/x
3. Step 3: Cross multiply
   1,559.61x = 2,152.29 × 860.99
4. Step 4: Simplify right side
   1,559.61x = 1,853,089.41
5. Step 5: Solve for x
   x = 1,853,089.41/1,559.61
6. Step 6: Final answer
   x = 1,188.17