Finding the Fourth Proportional to 13,388.86, 18,478.91 and 7,722.59

Step by Step Solution

1. Step 1: Write the proportion equation
   13,388.86 : 18,478.91 = 7,722.59 : x
2. Step 2: Convert to fraction form
   13,388.86/18,478.91 = 7,722.59/x
3. Step 3: Cross multiply
   13,388.86x = 18,478.91 × 7,722.59
4. Step 4: Simplify right side
   13,388.86x = 142,705,045.58
5. Step 5: Solve for x
   x = 142,705,045.58/13,388.86
6. Step 6: Final answer
   x = 10,658.49