Finding the Third Proportional to 78.38 and 105.56

Step by Step Solution

1. Step 1: Write the proportion equation
   78.38 : 105.56 = 105.56 : x
2. Step 2: Convert to fraction form
   78.38/105.56 = 105.56/x
3. Step 3: Cross multiply
   78.38x = 105.56 × 105.56
4. Step 4: Simplify right side
   78.38x = 11,143.44
5. Step 5: Solve for x
   x = 11,143.44/78.38
6. Step 6: Final answer
   x = 142.18