Finding the Third Proportional to 621,681 and 912,123

Step by Step Solution

1. Step 1: Write the proportion equation
   621,681 : 912,123 = 912,123 : x
2. Step 2: Convert to fraction form
   621,681/912,123 = 912,123/x
3. Step 3: Cross multiply
   621,681x = 912,123 × 912,123
4. Step 4: Simplify right side
   621,681x = 831,968,367,129
5. Step 5: Solve for x
   x = 831,968,367,129/621,681
6. Step 6: Final answer
   x = 1,338,256.06