Finding the Third Proportional to 142,290 and 213,060

Step by Step Solution

1. Step 1: Write the proportion equation
   142,290 : 213,060 = 213,060 : x
2. Step 2: Convert to fraction form
   142,290/213,060 = 213,060/x
3. Step 3: Cross multiply
   142,290x = 213,060 × 213,060
4. Step 4: Simplify right side
   142,290x = 45,394,563,600
5. Step 5: Solve for x
   x = 45,394,563,600/142,290
6. Step 6: Final answer
   x = 319,028.49