Finding the Fourth Proportional to 1,558.72, 2,151.18 and 860.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,558.72 : 2,151.18 = 860.09 : x
2. Step 2: Convert to fraction form
   1,558.72/2,151.18 = 860.09/x
3. Step 3: Cross multiply
   1,558.72x = 2,151.18 × 860.09
4. Step 4: Simplify right side
   1,558.72x = 1,850,208.41
5. Step 5: Solve for x
   x = 1,850,208.41/1,558.72
6. Step 6: Final answer
   x = 1,187.00