Finding the Third Proportional to 27.28 and 42.78

Step by Step Solution

1. Step 1: Write the proportion equation
   27.28 : 42.78 = 42.78 : x
2. Step 2: Convert to fraction form
   27.28/42.78 = 42.78/x
3. Step 3: Cross multiply
   27.28x = 42.78 × 42.78
4. Step 4: Simplify right side
   27.28x = 1,830.24
5. Step 5: Solve for x
   x = 1,830.24/27.28
6. Step 6: Final answer
   x = 67.09