Finding the Fourth Proportional to 1,186.78, 1,778.82 and 667.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,186.78 : 1,778.82 = 667.02 : x
2. Step 2: Convert to fraction form
   1,186.78/1,778.82 = 667.02/x
3. Step 3: Cross multiply
   1,186.78x = 1,778.82 × 667.02
4. Step 4: Simplify right side
   1,186.78x = 1,186,508.52
5. Step 5: Solve for x
   x = 1,186,508.52/1,186.78
6. Step 6: Final answer
   x = 999.77