Finding the Third Proportional to 42 and 42

Step by Step Solution

1. Step 1: Write the proportion equation
   42 : 42 = 42 : x
2. Step 2: Convert to fraction form
   42/42 = 42/x
3. Step 3: Cross multiply
   42x = 42 × 42
4. Step 4: Simplify right side
   42x = 1,764
5. Step 5: Solve for x
   x = 1,764/42
6. Step 6: Final answer
   x = 42