Finding the Fourth Proportional to 14,287.56, 21,429.70 and 3,900.12

Step by Step Solution

1. Step 1: Write the proportion equation
   14,287.56 : 21,429.70 = 3,900.12 : x
2. Step 2: Convert to fraction form
   14,287.56/21,429.70 = 3,900.12/x
3. Step 3: Cross multiply
   14,287.56x = 21,429.70 × 3,900.12
4. Step 4: Simplify right side
   14,287.56x = 83,578,401.56
5. Step 5: Solve for x
   x = 83,578,401.56/14,287.56
6. Step 6: Final answer
   x = 5,849.73