Finding the Fourth Proportional to 7,279.72, 10,911.75 and 3,121.54

Step by Step Solution

1. Step 1: Write the proportion equation
   7,279.72 : 10,911.75 = 3,121.54 : x
2. Step 2: Convert to fraction form
   7,279.72/10,911.75 = 3,121.54/x
3. Step 3: Cross multiply
   7,279.72x = 10,911.75 × 3,121.54
4. Step 4: Simplify right side
   7,279.72x = 34,061,464.10
5. Step 5: Solve for x
   x = 34,061,464.10/7,279.72
6. Step 6: Final answer
   x = 4,678.95