Finding the Third Proportional to 389,040 and 915,960

Step by Step Solution

1. Step 1: Write the proportion equation
   389,040 : 915,960 = 915,960 : x
2. Step 2: Convert to fraction form
   389,040/915,960 = 915,960/x
3. Step 3: Cross multiply
   389,040x = 915,960 × 915,960
4. Step 4: Simplify right side
   389,040x = 838,982,721,600
5. Step 5: Solve for x
   x = 838,982,721,600/389,040
6. Step 6: Final answer
   x = 2,156,546.17