Finding the Fourth Proportional to 1,558.39, 2,150.59 and 859.77

Step by Step Solution

1. Step 1: Write the proportion equation
   1,558.39 : 2,150.59 = 859.77 : x
2. Step 2: Convert to fraction form
   1,558.39/2,150.59 = 859.77/x
3. Step 3: Cross multiply
   1,558.39x = 2,150.59 × 859.77
4. Step 4: Simplify right side
   1,558.39x = 1,849,012.76
5. Step 5: Solve for x
   x = 1,849,012.76/1,558.39
6. Step 6: Final answer
   x = 1,186.49