Finding the Third Proportional to 199,200 and 428,608

Step by Step Solution

1. Step 1: Write the proportion equation
   199,200 : 428,608 = 428,608 : x
2. Step 2: Convert to fraction form
   199,200/428,608 = 428,608/x
3. Step 3: Cross multiply
   199,200x = 428,608 × 428,608
4. Step 4: Simplify right side
   199,200x = 183,704,817,664
5. Step 5: Solve for x
   x = 183,704,817,664/199,200
6. Step 6: Final answer
   x = 922,212.94