Finding the Third Proportional to 282,978 and 428,112

Step by Step Solution

1. Step 1: Write the proportion equation
   282,978 : 428,112 = 428,112 : x
2. Step 2: Convert to fraction form
   282,978/428,112 = 428,112/x
3. Step 3: Cross multiply
   282,978x = 428,112 × 428,112
4. Step 4: Simplify right side
   282,978x = 183,279,884,544
5. Step 5: Solve for x
   x = 183,279,884,544/282,978
6. Step 6: Final answer
   x = 647,682.45