Finding the Fourth Proportional to 999.42, 1,499.12 and 769.78

Step by Step Solution

1. Step 1: Write the proportion equation
   999.42 : 1,499.12 = 769.78 : x
2. Step 2: Convert to fraction form
   999.42/1,499.12 = 769.78/x
3. Step 3: Cross multiply
   999.42x = 1,499.12 × 769.78
4. Step 4: Simplify right side
   999.42x = 1,153,992.59
5. Step 5: Solve for x
   x = 1,153,992.59/999.42
6. Step 6: Final answer
   x = 1,154.66