Finding the Fourth Proportional to 5,139.12, 7,690.56 and 3,820.16

Step by Step Solution

1. Step 1: Write the proportion equation
   5,139.12 : 7,690.56 = 3,820.16 : x
2. Step 2: Convert to fraction form
   5,139.12/7,690.56 = 3,820.16/x
3. Step 3: Cross multiply
   5,139.12x = 7,690.56 × 3,820.16
4. Step 4: Simplify right side
   5,139.12x = 29,379,169.69
5. Step 5: Solve for x
   x = 29,379,169.69/5,139.12
6. Step 6: Final answer
   x = 5,716.77