Finding the Fourth Proportional to 13,680.54, 20,518.98 and 3,819

Step by Step Solution

1. Step 1: Write the proportion equation
   13,680.54 : 20,518.98 = 3,819 : x
2. Step 2: Convert to fraction form
   13,680.54/20,518.98 = 3,819/x
3. Step 3: Cross multiply
   13,680.54x = 20,518.98 × 3,819
4. Step 4: Simplify right side
   13,680.54x = 78,361,984.62
5. Step 5: Solve for x
   x = 78,361,984.62/13,680.54
6. Step 6: Final answer
   x = 5,727.99