Finding the Fourth Proportional to 1,228.10, 1,839.78 and 766.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,228.10 : 1,839.78 = 766.06 : x
2. Step 2: Convert to fraction form
   1,228.10/1,839.78 = 766.06/x
3. Step 3: Cross multiply
   1,228.10x = 1,839.78 × 766.06
4. Step 4: Simplify right side
   1,228.10x = 1,409,377.27
5. Step 5: Solve for x
   x = 1,409,377.27/1,228.10
6. Step 6: Final answer
   x = 1,147.61