Finding the Third Proportional to 299,782 and 642,300

Step by Step Solution

1. Step 1: Write the proportion equation
   299,782 : 642,300 = 642,300 : x
2. Step 2: Convert to fraction form
   299,782/642,300 = 642,300/x
3. Step 3: Cross multiply
   299,782x = 642,300 × 642,300
4. Step 4: Simplify right side
   299,782x = 412,549,290,000
5. Step 5: Solve for x
   x = 412,549,290,000/299,782
6. Step 6: Final answer
   x = 1,376,164.31