Finding the Fourth Proportional to 2,002.21, 3,003.49 and 521.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,002.21 : 3,003.49 = 521.43 : x
2. Step 2: Convert to fraction form
   2,002.21/3,003.49 = 521.43/x
3. Step 3: Cross multiply
   2,002.21x = 3,003.49 × 521.43
4. Step 4: Simplify right side
   2,002.21x = 1,566,109.79
5. Step 5: Solve for x
   x = 1,566,109.79/2,002.21
6. Step 6: Final answer
   x = 782.19