Finding the Fourth Proportional to 10,139.72, 15,205.50 and 3,899.96

Step by Step Solution

1. Step 1: Write the proportion equation
   10,139.72 : 15,205.50 = 3,899.96 : x
2. Step 2: Convert to fraction form
   10,139.72/15,205.50 = 3,899.96/x
3. Step 3: Cross multiply
   10,139.72x = 15,205.50 × 3,899.96
4. Step 4: Simplify right side
   10,139.72x = 59,300,841.78
5. Step 5: Solve for x
   x = 59,300,841.78/10,139.72
6. Step 6: Final answer
   x = 5,848.37