Finding the Fourth Proportional to 12,719.61, 19,078.20 and 7,786.71

Step by Step Solution

1. Step 1: Write the proportion equation
   12,719.61 : 19,078.20 = 7,786.71 : x
2. Step 2: Convert to fraction form
   12,719.61/19,078.20 = 7,786.71/x
3. Step 3: Cross multiply
   12,719.61x = 19,078.20 × 7,786.71
4. Step 4: Simplify right side
   12,719.61x = 148,556,410.72
5. Step 5: Solve for x
   x = 148,556,410.72/12,719.61
6. Step 6: Final answer
   x = 11,679.32