Finding the Third Proportional to 30,215 and 64,805

Step by Step Solution

1. Step 1: Write the proportion equation
   30,215 : 64,805 = 64,805 : x
2. Step 2: Convert to fraction form
   30,215/64,805 = 64,805/x
3. Step 3: Cross multiply
   30,215x = 64,805 × 64,805
4. Step 4: Simplify right side
   30,215x = 4,199,688,025
5. Step 5: Solve for x
   x = 4,199,688,025/30,215
6. Step 6: Final answer
   x = 138,993.48