Finding the Fourth Proportional to 1,398.48, 1,929.90 and 769.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,398.48 : 1,929.90 = 769.05 : x
2. Step 2: Convert to fraction form
   1,398.48/1,929.90 = 769.05/x
3. Step 3: Cross multiply
   1,398.48x = 1,929.90 × 769.05
4. Step 4: Simplify right side
   1,398.48x = 1,484,186.69
5. Step 5: Solve for x
   x = 1,484,186.69/1,398.48
6. Step 6: Final answer
   x = 1,061.29