Finding the Third Proportional to 139.13 and 189.56

Step by Step Solution

1. Step 1: Write the proportion equation
   139.13 : 189.56 = 189.56 : x
2. Step 2: Convert to fraction form
   139.13/189.56 = 189.56/x
3. Step 3: Cross multiply
   139.13x = 189.56 × 189.56
4. Step 4: Simplify right side
   139.13x = 35,933.94
5. Step 5: Solve for x
   x = 35,933.94/139.13
6. Step 6: Final answer
   x = 258.29