Finding the Third Proportional to 139 and 356.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139 : 356.50 = 356.50 : x
2. Step 2: Convert to fraction form
   139/356.50 = 356.50/x
3. Step 3: Cross multiply
   139x = 356.50 × 356.50
4. Step 4: Simplify right side
   139x = 127,092.25
5. Step 5: Solve for x
   x = 127,092.25/139
6. Step 6: Final answer
   x = 914.33