Finding the Third Proportional to 50,978 and 78,739

Step by Step Solution

1. Step 1: Write the proportion equation
   50,978 : 78,739 = 78,739 : x
2. Step 2: Convert to fraction form
   50,978/78,739 = 78,739/x
3. Step 3: Cross multiply
   50,978x = 78,739 × 78,739
4. Step 4: Simplify right side
   50,978x = 6,199,830,121
5. Step 5: Solve for x
   x = 6,199,830,121/50,978
6. Step 6: Final answer
   x = 121,617.76