Finding the Fourth Proportional to 7,979.82, 11,018.61 and 7,139.04

Step by Step Solution

1. Step 1: Write the proportion equation
   7,979.82 : 11,018.61 = 7,139.04 : x
2. Step 2: Convert to fraction form
   7,979.82/11,018.61 = 7,139.04/x
3. Step 3: Cross multiply
   7,979.82x = 11,018.61 × 7,139.04
4. Step 4: Simplify right side
   7,979.82x = 78,662,297.53
5. Step 5: Solve for x
   x = 78,662,297.53/7,979.82
6. Step 6: Final answer
   x = 9,857.65