Finding the Third Proportional to 428,322 and 627,123

Step by Step Solution

1. Step 1: Write the proportion equation
   428,322 : 627,123 = 627,123 : x
2. Step 2: Convert to fraction form
   428,322/627,123 = 627,123/x
3. Step 3: Cross multiply
   428,322x = 627,123 × 627,123
4. Step 4: Simplify right side
   428,322x = 393,283,257,129
5. Step 5: Solve for x
   x = 393,283,257,129/428,322
6. Step 6: Final answer
   x = 918,195.32