Finding the Fourth Proportional to 10,420.80, 14,380.56 and 5,704.80

Step by Step Solution

1. Step 1: Write the proportion equation
   10,420.80 : 14,380.56 = 5,704.80 : x
2. Step 2: Convert to fraction form
   10,420.80/14,380.56 = 5,704.80/x
3. Step 3: Cross multiply
   10,420.80x = 14,380.56 × 5,704.80
4. Step 4: Simplify right side
   10,420.80x = 82,038,218.69
5. Step 5: Solve for x
   x = 82,038,218.69/10,420.80
6. Step 6: Final answer
   x = 7,872.55