Finding the Third Proportional to 64,978 and 78,830

Step by Step Solution

1. Step 1: Write the proportion equation
   64,978 : 78,830 = 78,830 : x
2. Step 2: Convert to fraction form
   64,978/78,830 = 78,830/x
3. Step 3: Cross multiply
   64,978x = 78,830 × 78,830
4. Step 4: Simplify right side
   64,978x = 6,214,168,900
5. Step 5: Solve for x
   x = 6,214,168,900/64,978
6. Step 6: Final answer
   x = 95,634.97