Finding the Fourth Proportional to 42.21, 63.33 and 18.18

Step by Step Solution

1. Step 1: Write the proportion equation
   42.21 : 63.33 = 18.18 : x
2. Step 2: Convert to fraction form
   42.21/63.33 = 18.18/x
3. Step 3: Cross multiply
   42.21x = 63.33 × 18.18
4. Step 4: Simplify right side
   42.21x = 1,151.34
5. Step 5: Solve for x
   x = 1,151.34/42.21
6. Step 6: Final answer
   x = 27.28