Finding the Third Proportional to 42.71 and 86.38

Step by Step Solution

1. Step 1: Write the proportion equation
   42.71 : 86.38 = 86.38 : x
2. Step 2: Convert to fraction form
   42.71/86.38 = 86.38/x
3. Step 3: Cross multiply
   42.71x = 86.38 × 86.38
4. Step 4: Simplify right side
   42.71x = 7,461.32
5. Step 5: Solve for x
   x = 7,461.32/42.71
6. Step 6: Final answer
   x = 174.68