Finding the Third Proportional to 145.78 and 322.78

Step by Step Solution

1. Step 1: Write the proportion equation
   145.78 : 322.78 = 322.78 : x
2. Step 2: Convert to fraction form
   145.78/322.78 = 322.78/x
3. Step 3: Cross multiply
   145.78x = 322.78 × 322.78
4. Step 4: Simplify right side
   145.78x = 104,187.74
5. Step 5: Solve for x
   x = 104,187.74/145.78
6. Step 6: Final answer
   x = 714.69