Finding the Third Proportional to 31,878 and 65,821.50

Step by Step Solution

1. Step 1: Write the proportion equation
   31,878 : 65,821.50 = 65,821.50 : x
2. Step 2: Convert to fraction form
   31,878/65,821.50 = 65,821.50/x
3. Step 3: Cross multiply
   31,878x = 65,821.50 × 65,821.50
4. Step 4: Simplify right side
   31,878x = 4,332,469,862.25
5. Step 5: Solve for x
   x = 4,332,469,862.25/31,878
6. Step 6: Final answer
   x = 135,907.83