Finding the Fourth Proportional to 14,479.20, 21,721.20 and 5,118.72

Step by Step Solution

1. Step 1: Write the proportion equation
   14,479.20 : 21,721.20 = 5,118.72 : x
2. Step 2: Convert to fraction form
   14,479.20/21,721.20 = 5,118.72/x
3. Step 3: Cross multiply
   14,479.20x = 21,721.20 × 5,118.72
4. Step 4: Simplify right side
   14,479.20x = 111,184,740.86
5. Step 5: Solve for x
   x = 111,184,740.86/14,479.20
6. Step 6: Final answer
   x = 7,678.93