Finding the Fourth Proportional to 1,189.08, 1,786.05 and 778.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,189.08 : 1,786.05 = 778.82 : x
2. Step 2: Convert to fraction form
   1,189.08/1,786.05 = 778.82/x
3. Step 3: Cross multiply
   1,189.08x = 1,786.05 × 778.82
4. Step 4: Simplify right side
   1,189.08x = 1,391,002.53
5. Step 5: Solve for x
   x = 1,391,002.53/1,189.08
6. Step 6: Final answer
   x = 1,169.81