Finding the Fourth Proportional to 13,839.61, 19,099.69 and 7,873.20

Step by Step Solution

1. Step 1: Write the proportion equation
   13,839.61 : 19,099.69 = 7,873.20 : x
2. Step 2: Convert to fraction form
   13,839.61/19,099.69 = 7,873.20/x
3. Step 3: Cross multiply
   13,839.61x = 19,099.69 × 7,873.20
4. Step 4: Simplify right side
   13,839.61x = 150,375,648.55
5. Step 5: Solve for x
   x = 150,375,648.55/13,839.61
6. Step 6: Final answer
   x = 10,865.60