Finding the Fourth Proportional to 15,285, 21,128.61 and 12,752.34

Step by Step Solution

1. Step 1: Write the proportion equation
   15,285 : 21,128.61 = 12,752.34 : x
2. Step 2: Convert to fraction form
   15,285/21,128.61 = 12,752.34/x
3. Step 3: Cross multiply
   15,285x = 21,128.61 × 12,752.34
4. Step 4: Simplify right side
   15,285x = 269,439,218.45
5. Step 5: Solve for x
   x = 269,439,218.45/15,285
6. Step 6: Final answer
   x = 17,627.69