Finding the Third Proportional to 143.72 and 298.69

Step by Step Solution

1. Step 1: Write the proportion equation
   143.72 : 298.69 = 298.69 : x
2. Step 2: Convert to fraction form
   143.72/298.69 = 298.69/x
3. Step 3: Cross multiply
   143.72x = 298.69 × 298.69
4. Step 4: Simplify right side
   143.72x = 89,214.22
5. Step 5: Solve for x
   x = 89,214.22/143.72
6. Step 6: Final answer
   x = 620.76