Finding the Third Proportional to 2.79 and 3.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2.79 : 3.89 = 3.89 : x
2. Step 2: Convert to fraction form
   2.79/3.89 = 3.89/x
3. Step 3: Cross multiply
   2.79x = 3.89 × 3.89
4. Step 4: Simplify right side
   2.79x = 15.15
5. Step 5: Solve for x
   x = 15.15/2.79
6. Step 6: Final answer
   x = 5.44