Finding the Fourth Proportional to 2,629.21, 3,944.47 and 780.32

Step by Step Solution

1. Step 1: Write the proportion equation
   2,629.21 : 3,944.47 = 780.32 : x
2. Step 2: Convert to fraction form
   2,629.21/3,944.47 = 780.32/x
3. Step 3: Cross multiply
   2,629.21x = 3,944.47 × 780.32
4. Step 4: Simplify right side
   2,629.21x = 3,077,964.86
5. Step 5: Solve for x
   x = 3,077,964.86/2,629.21
6. Step 6: Final answer
   x = 1,170.68