Finding the Third Proportional to 20,876,264,640,978 and 42,347,790,101,766

Step by Step Solution

1. Step 1: Write the proportion equation
   20,876,264,640,978 : 42,347,790,101,766 = 42,347,790,101,766 : x
2. Step 2: Convert to fraction form
   20,876,264,640,978/42,347,790,101,766 = 42,347,790,101,766/x
3. Step 3: Cross multiply
   20,876,264,640,978x = 42,347,790,101,766 × 42,347,790,101,766
4. Step 4: Simplify right side
   20,876,264,640,978x = 1,793,335,326,503,230,485,666,201,600
5. Step 5: Solve for x
   x = 1,793,335,326,503,230,485,666,201,600/20,876,264,640,978
6. Step 6: Final answer
   x = 85,903,074,967,879.75