Finding the Third Proportional to 401.50 and 539.50

Step by Step Solution

1. Step 1: Write the proportion equation
   401.50 : 539.50 = 539.50 : x
2. Step 2: Convert to fraction form
   401.50/539.50 = 539.50/x
3. Step 3: Cross multiply
   401.50x = 539.50 × 539.50
4. Step 4: Simplify right side
   401.50x = 291,060.25
5. Step 5: Solve for x
   x = 291,060.25/401.50
6. Step 6: Final answer
   x = 724.93