Finding the Third Proportional to 139.69 and 213.13

Step by Step Solution

1. Step 1: Write the proportion equation
   139.69 : 213.13 = 213.13 : x
2. Step 2: Convert to fraction form
   139.69/213.13 = 213.13/x
3. Step 3: Cross multiply
   139.69x = 213.13 × 213.13
4. Step 4: Simplify right side
   139.69x = 45,422.27
5. Step 5: Solve for x
   x = 45,422.27/139.69
6. Step 6: Final answer
   x = 325.17