Finding the Third Proportional to 427.50 and 617.25

Step by Step Solution

1. Step 1: Write the proportion equation
   427.50 : 617.25 = 617.25 : x
2. Step 2: Convert to fraction form
   427.50/617.25 = 617.25/x
3. Step 3: Cross multiply
   427.50x = 617.25 × 617.25
4. Step 4: Simplify right side
   427.50x = 380,997.56
5. Step 5: Solve for x
   x = 380,997.56/427.50
6. Step 6: Final answer
   x = 891.22