Finding the Fourth Proportional to 21,222.56, 29,256.72 and 14,915.36

Step by Step Solution

1. Step 1: Write the proportion equation
   21,222.56 : 29,256.72 = 14,915.36 : x
2. Step 2: Convert to fraction form
   21,222.56/29,256.72 = 14,915.36/x
3. Step 3: Cross multiply
   21,222.56x = 29,256.72 × 14,915.36
4. Step 4: Simplify right side
   21,222.56x = 436,374,511.22
5. Step 5: Solve for x
   x = 436,374,511.22/21,222.56
6. Step 6: Final answer
   x = 20,561.82