Finding the Third Proportional to 142.44 and 256.56

Step by Step Solution

1. Step 1: Write the proportion equation
   142.44 : 256.56 = 256.56 : x
2. Step 2: Convert to fraction form
   142.44/256.56 = 256.56/x
3. Step 3: Cross multiply
   142.44x = 256.56 × 256.56
4. Step 4: Simplify right side
   142.44x = 65,824.32
5. Step 5: Solve for x
   x = 65,824.32/142.44
6. Step 6: Final answer
   x = 462.13