Finding the Fourth Proportional to 21,456.96, 32,178.80 and 10,356.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,456.96 : 32,178.80 = 10,356.72 : x
2. Step 2: Convert to fraction form
   21,456.96/32,178.80 = 10,356.72/x
3. Step 3: Cross multiply
   21,456.96x = 32,178.80 × 10,356.72
4. Step 4: Simplify right side
   21,456.96x = 333,266,821.54
5. Step 5: Solve for x
   x = 333,266,821.54/21,456.96
6. Step 6: Final answer
   x = 15,531.88