Finding the Third Proportional to 131.25 and 318.75

Step by Step Solution

1. Step 1: Write the proportion equation
   131.25 : 318.75 = 318.75 : x
2. Step 2: Convert to fraction form
   131.25/318.75 = 318.75/x
3. Step 3: Cross multiply
   131.25x = 318.75 × 318.75
4. Step 4: Simplify right side
   131.25x = 101,601.56
5. Step 5: Solve for x
   x = 101,601.56/131.25
6. Step 6: Final answer
   x = 774.11