Finding the Fourth Proportional to 42.18, 63.24 and 31.33

Step by Step Solution

1. Step 1: Write the proportion equation
   42.18 : 63.24 = 31.33 : x
2. Step 2: Convert to fraction form
   42.18/63.24 = 31.33/x
3. Step 3: Cross multiply
   42.18x = 63.24 × 31.33
4. Step 4: Simplify right side
   42.18x = 1,981.31
5. Step 5: Solve for x
   x = 1,981.31/42.18
6. Step 6: Final answer
   x = 46.97