Finding the Fourth Proportional to 18,643.96, 25,728.78 and 10,146.15

Step by Step Solution

1. Step 1: Write the proportion equation
   18,643.96 : 25,728.78 = 10,146.15 : x
2. Step 2: Convert to fraction form
   18,643.96/25,728.78 = 10,146.15/x
3. Step 3: Cross multiply
   18,643.96x = 25,728.78 × 10,146.15
4. Step 4: Simplify right side
   18,643.96x = 261,047,978.31
5. Step 5: Solve for x
   x = 261,047,978.31/18,643.96
6. Step 6: Final answer
   x = 14,001.75