Finding the Fourth Proportional to 42.28, 63.46 and 21.98

Step by Step Solution

1. Step 1: Write the proportion equation
   42.28 : 63.46 = 21.98 : x
2. Step 2: Convert to fraction form
   42.28/63.46 = 21.98/x
3. Step 3: Cross multiply
   42.28x = 63.46 × 21.98
4. Step 4: Simplify right side
   42.28x = 1,394.85
5. Step 5: Solve for x
   x = 1,394.85/42.28
6. Step 6: Final answer
   x = 32.99