Finding the Fourth Proportional to 2,630.79, 3,945.50 and 781.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,630.79 : 3,945.50 = 781.47 : x
2. Step 2: Convert to fraction form
   2,630.79/3,945.50 = 781.47/x
3. Step 3: Cross multiply
   2,630.79x = 3,945.50 × 781.47
4. Step 4: Simplify right side
   2,630.79x = 3,083,291.84
5. Step 5: Solve for x
   x = 3,083,291.84/2,630.79
6. Step 6: Final answer
   x = 1,172.00