Finding the Fourth Proportional to 1,559.34, 2,151.72 and 860.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.34 : 2,151.72 = 860.58 : x
2. Step 2: Convert to fraction form
   1,559.34/2,151.72 = 860.58/x
3. Step 3: Cross multiply
   1,559.34x = 2,151.72 × 860.58
4. Step 4: Simplify right side
   1,559.34x = 1,851,727.20
5. Step 5: Solve for x
   x = 1,851,727.20/1,559.34
6. Step 6: Final answer
   x = 1,187.51