Finding the Third Proportional to 9,920,638 and 21,258,440

Step by Step Solution

1. Step 1: Write the proportion equation
   9,920,638 : 21,258,440 = 21,258,440 : x
2. Step 2: Convert to fraction form
   9,920,638/21,258,440 = 21,258,440/x
3. Step 3: Cross multiply
   9,920,638x = 21,258,440 × 21,258,440
4. Step 4: Simplify right side
   9,920,638x = 451,921,271,233,600
5. Step 5: Solve for x
   x = 451,921,271,233,600/9,920,638
6. Step 6: Final answer
   x = 45,553,650.00