Finding the Third Proportional to 69 and 142

Step by Step Solution

1. Step 1: Write the proportion equation
   69 : 142 = 142 : x
2. Step 2: Convert to fraction form
   69/142 = 142/x
3. Step 3: Cross multiply
   69x = 142 × 142
4. Step 4: Simplify right side
   69x = 20,164
5. Step 5: Solve for x
   x = 20,164/69
6. Step 6: Final answer
   x = 292.23