Finding the Fourth Proportional to 1,383.76, 1,909.64 and 762.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.76 : 1,909.64 = 762.80 : x
2. Step 2: Convert to fraction form
   1,383.76/1,909.64 = 762.80/x
3. Step 3: Cross multiply
   1,383.76x = 1,909.64 × 762.80
4. Step 4: Simplify right side
   1,383.76x = 1,456,673.39
5. Step 5: Solve for x
   x = 1,456,673.39/1,383.76
6. Step 6: Final answer
   x = 1,052.69