Finding the Third Proportional to 208,899 and 428,858

Step by Step Solution

1. Step 1: Write the proportion equation
   208,899 : 428,858 = 428,858 : x
2. Step 2: Convert to fraction form
   208,899/428,858 = 428,858/x
3. Step 3: Cross multiply
   208,899x = 428,858 × 428,858
4. Step 4: Simplify right side
   208,899x = 183,919,184,164
5. Step 5: Solve for x
   x = 183,919,184,164/208,899
6. Step 6: Final answer
   x = 880,421.56