Finding the Third Proportional to 61.78 and 133.69

Step by Step Solution

1. Step 1: Write the proportion equation
   61.78 : 133.69 = 133.69 : x
2. Step 2: Convert to fraction form
   61.78/133.69 = 133.69/x
3. Step 3: Cross multiply
   61.78x = 133.69 × 133.69
4. Step 4: Simplify right side
   61.78x = 17,872.35
5. Step 5: Solve for x
   x = 17,872.35/61.78
6. Step 6: Final answer
   x = 289.28