Finding the Third Proportional to 78.56 and 124.69

Step by Step Solution

1. Step 1: Write the proportion equation
   78.56 : 124.69 = 124.69 : x
2. Step 2: Convert to fraction form
   78.56/124.69 = 124.69/x
3. Step 3: Cross multiply
   78.56x = 124.69 × 124.69
4. Step 4: Simplify right side
   78.56x = 15,546.97
5. Step 5: Solve for x
   x = 15,546.97/78.56
6. Step 6: Final answer
   x = 197.89