Finding the Third Proportional to 308.69 and 400.88

Step by Step Solution

1. Step 1: Write the proportion equation
   308.69 : 400.88 = 400.88 : x
2. Step 2: Convert to fraction form
   308.69/400.88 = 400.88/x
3. Step 3: Cross multiply
   308.69x = 400.88 × 400.88
4. Step 4: Simplify right side
   308.69x = 160,700.77
5. Step 5: Solve for x
   x = 160,700.77/308.69
6. Step 6: Final answer
   x = 520.59