Finding the Third Proportional to 19,686 and 42,288

Step by Step Solution

1. Step 1: Write the proportion equation
   19,686 : 42,288 = 42,288 : x
2. Step 2: Convert to fraction form
   19,686/42,288 = 42,288/x
3. Step 3: Cross multiply
   19,686x = 42,288 × 42,288
4. Step 4: Simplify right side
   19,686x = 1,788,274,944
5. Step 5: Solve for x
   x = 1,788,274,944/19,686
6. Step 6: Final answer
   x = 90,839.93