Finding the Fourth Proportional to 42.42, 63.60 and 16.72

Step by Step Solution

1. Step 1: Write the proportion equation
   42.42 : 63.60 = 16.72 : x
2. Step 2: Convert to fraction form
   42.42/63.60 = 16.72/x
3. Step 3: Cross multiply
   42.42x = 63.60 × 16.72
4. Step 4: Simplify right side
   42.42x = 1,063.39
5. Step 5: Solve for x
   x = 1,063.39/42.42
6. Step 6: Final answer
   x = 25.07