Finding the Third Proportional to 150.56 and 319.69

Step by Step Solution

1. Step 1: Write the proportion equation
   150.56 : 319.69 = 319.69 : x
2. Step 2: Convert to fraction form
   150.56/319.69 = 319.69/x
3. Step 3: Cross multiply
   150.56x = 319.69 × 319.69
4. Step 4: Simplify right side
   150.56x = 102,200.10
5. Step 5: Solve for x
   x = 102,200.10/150.56
6. Step 6: Final answer
   x = 678.79