Finding the Third Proportional to 19,978 and 28,122

Step by Step Solution

1. Step 1: Write the proportion equation
   19,978 : 28,122 = 28,122 : x
2. Step 2: Convert to fraction form
   19,978/28,122 = 28,122/x
3. Step 3: Cross multiply
   19,978x = 28,122 × 28,122
4. Step 4: Simplify right side
   19,978x = 790,846,884
5. Step 5: Solve for x
   x = 790,846,884/19,978
6. Step 6: Final answer
   x = 39,585.89