Finding the Third Proportional to 142,034.50 and 312,090

Step by Step Solution

1. Step 1: Write the proportion equation
   142,034.50 : 312,090 = 312,090 : x
2. Step 2: Convert to fraction form
   142,034.50/312,090 = 312,090/x
3. Step 3: Cross multiply
   142,034.50x = 312,090 × 312,090
4. Step 4: Simplify right side
   142,034.50x = 97,400,168,100
5. Step 5: Solve for x
   x = 97,400,168,100/142,034.50
6. Step 6: Final answer
   x = 685,750.07