Finding the Fourth Proportional to 1,087.72, 1,498.96 and 776.68

Step by Step Solution

1. Step 1: Write the proportion equation
   1,087.72 : 1,498.96 = 776.68 : x
2. Step 2: Convert to fraction form
   1,087.72/1,498.96 = 776.68/x
3. Step 3: Cross multiply
   1,087.72x = 1,498.96 × 776.68
4. Step 4: Simplify right side
   1,087.72x = 1,164,212.25
5. Step 5: Solve for x
   x = 1,164,212.25/1,087.72
6. Step 6: Final answer
   x = 1,070.32