Finding the Third Proportional to 142,020 and 312,066

Step by Step Solution

1. Step 1: Write the proportion equation
   142,020 : 312,066 = 312,066 : x
2. Step 2: Convert to fraction form
   142,020/312,066 = 312,066/x
3. Step 3: Cross multiply
   142,020x = 312,066 × 312,066
4. Step 4: Simplify right side
   142,020x = 97,385,188,356
5. Step 5: Solve for x
   x = 97,385,188,356/142,020
6. Step 6: Final answer
   x = 685,714.61