Finding the Third Proportional to 0.42 and 0.42

Step by Step Solution

1. Step 1: Write the proportion equation
   0.42 : 0.42 = 0.42 : x
2. Step 2: Convert to fraction form
   0.42/0.42 = 0.42/x
3. Step 3: Cross multiply
   0.42x = 0.42 × 0.42
4. Step 4: Simplify right side
   0.42x = 0.18
5. Step 5: Solve for x
   x = 0.18/0.42
6. Step 6: Final answer
   x = 0.42