Finding the Fourth Proportional to 1,558.50, 2,150.78 and 859.92

Step by Step Solution

1. Step 1: Write the proportion equation
   1,558.50 : 2,150.78 = 859.92 : x
2. Step 2: Convert to fraction form
   1,558.50/2,150.78 = 859.92/x
3. Step 3: Cross multiply
   1,558.50x = 2,150.78 × 859.92
4. Step 4: Simplify right side
   1,558.50x = 1,849,494.44
5. Step 5: Solve for x
   x = 1,849,494.44/1,558.50
6. Step 6: Final answer
   x = 1,186.71