Finding the Third Proportional to 148.69 and 320.25

Step by Step Solution

1. Step 1: Write the proportion equation
   148.69 : 320.25 = 320.25 : x
2. Step 2: Convert to fraction form
   148.69/320.25 = 320.25/x
3. Step 3: Cross multiply
   148.69x = 320.25 × 320.25
4. Step 4: Simplify right side
   148.69x = 102,560.06
5. Step 5: Solve for x
   x = 102,560.06/148.69
6. Step 6: Final answer
   x = 689.77