Finding the Third Proportional to 143.46 and 312.54

Step by Step Solution

1. Step 1: Write the proportion equation
   143.46 : 312.54 = 312.54 : x
2. Step 2: Convert to fraction form
   143.46/312.54 = 312.54/x
3. Step 3: Cross multiply
   143.46x = 312.54 × 312.54
4. Step 4: Simplify right side
   143.46x = 97,680.67
5. Step 5: Solve for x
   x = 97,680.67/143.46
6. Step 6: Final answer
   x = 680.89