Finding the Third Proportional to 55.78 and 128.06

Step by Step Solution

1. Step 1: Write the proportion equation
   55.78 : 128.06 = 128.06 : x
2. Step 2: Convert to fraction form
   55.78/128.06 = 128.06/x
3. Step 3: Cross multiply
   55.78x = 128.06 × 128.06
4. Step 4: Simplify right side
   55.78x = 16,400.00
5. Step 5: Solve for x
   x = 16,400.00/55.78
6. Step 6: Final answer
   x = 294.01