Finding the Fourth Proportional to 7,820.43, 11,729.25 and 3,870.42

Step by Step Solution

1. Step 1: Write the proportion equation
   7,820.43 : 11,729.25 = 3,870.42 : x
2. Step 2: Convert to fraction form
   7,820.43/11,729.25 = 3,870.42/x
3. Step 3: Cross multiply
   7,820.43x = 11,729.25 × 3,870.42
4. Step 4: Simplify right side
   7,820.43x = 45,397,123.79
5. Step 5: Solve for x
   x = 45,397,123.79/7,820.43
6. Step 6: Final answer
   x = 5,804.94