Finding the Fourth Proportional to 42.57, 63.50 and 42.12

Step by Step Solution

1. Step 1: Write the proportion equation
   42.57 : 63.50 = 42.12 : x
2. Step 2: Convert to fraction form
   42.57/63.50 = 42.12/x
3. Step 3: Cross multiply
   42.57x = 63.50 × 42.12
4. Step 4: Simplify right side
   42.57x = 2,674.41
5. Step 5: Solve for x
   x = 2,674.41/42.57
6. Step 6: Final answer
   x = 62.82