Finding the Third Proportional to 199,806 and 428,111

Step by Step Solution

1. Step 1: Write the proportion equation
   199,806 : 428,111 = 428,111 : x
2. Step 2: Convert to fraction form
   199,806/428,111 = 428,111/x
3. Step 3: Cross multiply
   199,806x = 428,111 × 428,111
4. Step 4: Simplify right side
   199,806x = 183,279,028,321
5. Step 5: Solve for x
   x = 183,279,028,321/199,806
6. Step 6: Final answer
   x = 917,284.91