Finding the Third Proportional to 31 and 72

Step by Step Solution

1. Step 1: Write the proportion equation
   31 : 72 = 72 : x
2. Step 2: Convert to fraction form
   31/72 = 72/x
3. Step 3: Cross multiply
   31x = 72 × 72
4. Step 4: Simplify right side
   31x = 5,184
5. Step 5: Solve for x
   x = 5,184/31
6. Step 6: Final answer
   x = 167.23