Finding the Fourth Proportional to 738.79, 1,105.61 and 521.98

Step by Step Solution

1. Step 1: Write the proportion equation
   738.79 : 1,105.61 = 521.98 : x
2. Step 2: Convert to fraction form
   738.79/1,105.61 = 521.98/x
3. Step 3: Cross multiply
   738.79x = 1,105.61 × 521.98
4. Step 4: Simplify right side
   738.79x = 577,100.78
5. Step 5: Solve for x
   x = 577,100.78/738.79
6. Step 6: Final answer
   x = 781.15