Finding the Third Proportional to 21,978 and 51,853

Step by Step Solution

1. Step 1: Write the proportion equation
   21,978 : 51,853 = 51,853 : x
2. Step 2: Convert to fraction form
   21,978/51,853 = 51,853/x
3. Step 3: Cross multiply
   21,978x = 51,853 × 51,853
4. Step 4: Simplify right side
   21,978x = 2,688,733,609
5. Step 5: Solve for x
   x = 2,688,733,609/21,978
6. Step 6: Final answer
   x = 122,337.50