Finding the Third Proportional to 3,111.75 and 4,120.88

Step by Step Solution

1. Step 1: Write the proportion equation
   3,111.75 : 4,120.88 = 4,120.88 : x
2. Step 2: Convert to fraction form
   3,111.75/4,120.88 = 4,120.88/x
3. Step 3: Cross multiply
   3,111.75x = 4,120.88 × 4,120.88
4. Step 4: Simplify right side
   3,111.75x = 16,981,610.77
5. Step 5: Solve for x
   x = 16,981,610.77/3,111.75
6. Step 6: Final answer
   x = 5,457.25