Finding the Fourth Proportional to 42.86, 63.84 and 42.39

Step by Step Solution

1. Step 1: Write the proportion equation
   42.86 : 63.84 = 42.39 : x
2. Step 2: Convert to fraction form
   42.86/63.84 = 42.39/x
3. Step 3: Cross multiply
   42.86x = 63.84 × 42.39
4. Step 4: Simplify right side
   42.86x = 2,706.18
5. Step 5: Solve for x
   x = 2,706.18/42.86
6. Step 6: Final answer
   x = 63.14