Finding the Fourth Proportional to 1,006.96, 1,507.68 and 762.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,006.96 : 1,507.68 = 762.78 : x
2. Step 2: Convert to fraction form
   1,006.96/1,507.68 = 762.78/x
3. Step 3: Cross multiply
   1,006.96x = 1,507.68 × 762.78
4. Step 4: Simplify right side
   1,006.96x = 1,150,028.15
5. Step 5: Solve for x
   x = 1,150,028.15/1,006.96
6. Step 6: Final answer
   x = 1,142.08