Finding the Fourth Proportional to 21,878.78, 30,172.23 and 17,417.30

Step by Step Solution

1. Step 1: Write the proportion equation
   21,878.78 : 30,172.23 = 17,417.30 : x
2. Step 2: Convert to fraction form
   21,878.78/30,172.23 = 17,417.30/x
3. Step 3: Cross multiply
   21,878.78x = 30,172.23 × 17,417.30
4. Step 4: Simplify right side
   21,878.78x = 525,518,630.72
5. Step 5: Solve for x
   x = 525,518,630.72/21,878.78
6. Step 6: Final answer
   x = 24,019.56