Finding the Fourth Proportional to 2,628.91, 3,944.13 and 780.07

Step by Step Solution

1. Step 1: Write the proportion equation
   2,628.91 : 3,944.13 = 780.07 : x
2. Step 2: Convert to fraction form
   2,628.91/3,944.13 = 780.07/x
3. Step 3: Cross multiply
   2,628.91x = 3,944.13 × 780.07
4. Step 4: Simplify right side
   2,628.91x = 3,076,677.77
5. Step 5: Solve for x
   x = 3,076,677.77/2,628.91
6. Step 6: Final answer
   x = 1,170.33