Finding the Third Proportional to 61.50 and 129.56

Step by Step Solution

1. Step 1: Write the proportion equation
   61.50 : 129.56 = 129.56 : x
2. Step 2: Convert to fraction form
   61.50/129.56 = 129.56/x
3. Step 3: Cross multiply
   61.50x = 129.56 × 129.56
4. Step 4: Simplify right side
   61.50x = 16,786.44
5. Step 5: Solve for x
   x = 16,786.44/61.50
6. Step 6: Final answer
   x = 272.95