Finding the Third Proportional to 2,138,440 and 4,428,457

Step by Step Solution

1. Step 1: Write the proportion equation
   2,138,440 : 4,428,457 = 4,428,457 : x
2. Step 2: Convert to fraction form
   2,138,440/4,428,457 = 4,428,457/x
3. Step 3: Cross multiply
   2,138,440x = 4,428,457 × 4,428,457
4. Step 4: Simplify right side
   2,138,440x = 19,611,231,400,849
5. Step 5: Solve for x
   x = 19,611,231,400,849/2,138,440
6. Step 6: Final answer
   x = 9,170,812.09