Finding the Third Proportional to 142,808 and 213,780

Step by Step Solution

1. Step 1: Write the proportion equation
   142,808 : 213,780 = 213,780 : x
2. Step 2: Convert to fraction form
   142,808/213,780 = 213,780/x
3. Step 3: Cross multiply
   142,808x = 213,780 × 213,780
4. Step 4: Simplify right side
   142,808x = 45,701,888,400
5. Step 5: Solve for x
   x = 45,701,888,400/142,808
6. Step 6: Final answer
   x = 320,023.31