Finding the Third Proportional to 20,978 and 45,638

Step by Step Solution

1. Step 1: Write the proportion equation
   20,978 : 45,638 = 45,638 : x
2. Step 2: Convert to fraction form
   20,978/45,638 = 45,638/x
3. Step 3: Cross multiply
   20,978x = 45,638 × 45,638
4. Step 4: Simplify right side
   20,978x = 2,082,827,044
5. Step 5: Solve for x
   x = 2,082,827,044/20,978
6. Step 6: Final answer
   x = 99,286.25