Finding the Fourth Proportional to 1,150.89, 1,587.59 and 778.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,150.89 : 1,587.59 = 778.40 : x
2. Step 2: Convert to fraction form
   1,150.89/1,587.59 = 778.40/x
3. Step 3: Cross multiply
   1,150.89x = 1,587.59 × 778.40
4. Step 4: Simplify right side
   1,150.89x = 1,235,774.06
5. Step 5: Solve for x
   x = 1,235,774.06/1,150.89
6. Step 6: Final answer
   x = 1,073.76