Finding the Fourth Proportional to 13,279.16, 18,321.18 and 7,689.08

Step by Step Solution

1. Step 1: Write the proportion equation
   13,279.16 : 18,321.18 = 7,689.08 : x
2. Step 2: Convert to fraction form
   13,279.16/18,321.18 = 7,689.08/x
3. Step 3: Cross multiply
   13,279.16x = 18,321.18 × 7,689.08
4. Step 4: Simplify right side
   13,279.16x = 140,873,018.71
5. Step 5: Solve for x
   x = 140,873,018.71/13,279.16
6. Step 6: Final answer
   x = 10,608.58