Finding the Third Proportional to 139.25 and 248.25

Step by Step Solution

1. Step 1: Write the proportion equation
   139.25 : 248.25 = 248.25 : x
2. Step 2: Convert to fraction form
   139.25/248.25 = 248.25/x
3. Step 3: Cross multiply
   139.25x = 248.25 × 248.25
4. Step 4: Simplify right side
   139.25x = 61,628.06
5. Step 5: Solve for x
   x = 61,628.06/139.25
6. Step 6: Final answer
   x = 442.57