Finding the Third Proportional to 3,370.78 and 5,128.31

Step by Step Solution

1. Step 1: Write the proportion equation
   3,370.78 : 5,128.31 = 5,128.31 : x
2. Step 2: Convert to fraction form
   3,370.78/5,128.31 = 5,128.31/x
3. Step 3: Cross multiply
   3,370.78x = 5,128.31 × 5,128.31
4. Step 4: Simplify right side
   3,370.78x = 26,299,589.10
5. Step 5: Solve for x
   x = 26,299,589.10/3,370.78
6. Step 6: Final answer
   x = 7,802.22