Finding the Third Proportional to 123.21 and 145.71

Step by Step Solution

1. Step 1: Write the proportion equation
   123.21 : 145.71 = 145.71 : x
2. Step 2: Convert to fraction form
   123.21/145.71 = 145.71/x
3. Step 3: Cross multiply
   123.21x = 145.71 × 145.71
4. Step 4: Simplify right side
   123.21x = 21,229.97
5. Step 5: Solve for x
   x = 21,229.97/123.21
6. Step 6: Final answer
   x = 172.31