Finding the Third Proportional to 142.31 and 276.75

Step by Step Solution

1. Step 1: Write the proportion equation
   142.31 : 276.75 = 276.75 : x
2. Step 2: Convert to fraction form
   142.31/276.75 = 276.75/x
3. Step 3: Cross multiply
   142.31x = 276.75 × 276.75
4. Step 4: Simplify right side
   142.31x = 76,590.56
5. Step 5: Solve for x
   x = 76,590.56/142.31
6. Step 6: Final answer
   x = 538.19