Finding the Fourth Proportional to 13,828.90, 19,085.50 and 7,861.47

Step by Step Solution

1. Step 1: Write the proportion equation
   13,828.90 : 19,085.50 = 7,861.47 : x
2. Step 2: Convert to fraction form
   13,828.90/19,085.50 = 7,861.47/x
3. Step 3: Cross multiply
   13,828.90x = 19,085.50 × 7,861.47
4. Step 4: Simplify right side
   13,828.90x = 150,040,078.42
5. Step 5: Solve for x
   x = 150,040,078.42/13,828.90
6. Step 6: Final answer
   x = 10,849.75