Finding the Third Proportional to 2.59 and 3.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2.59 : 3.91 = 3.91 : x
2. Step 2: Convert to fraction form
   2.59/3.91 = 3.91/x
3. Step 3: Cross multiply
   2.59x = 3.91 × 3.91
4. Step 4: Simplify right side
   2.59x = 15.25
5. Step 5: Solve for x
   x = 15.25/2.59
6. Step 6: Final answer
   x = 5.90