Finding the Fourth Proportional to 21,860.82, 30,168.24 and 12,429.36

Step by Step Solution

1. Step 1: Write the proportion equation
   21,860.82 : 30,168.24 = 12,429.36 : x
2. Step 2: Convert to fraction form
   21,860.82/30,168.24 = 12,429.36/x
3. Step 3: Cross multiply
   21,860.82x = 30,168.24 × 12,429.36
4. Step 4: Simplify right side
   21,860.82x = 374,971,915.53
5. Step 5: Solve for x
   x = 374,971,915.53/21,860.82
6. Step 6: Final answer
   x = 17,152.69