Finding the Fourth Proportional to 71.39, 106.77 and 42.43

Step by Step Solution

1. Step 1: Write the proportion equation
   71.39 : 106.77 = 42.43 : x
2. Step 2: Convert to fraction form
   71.39/106.77 = 42.43/x
3. Step 3: Cross multiply
   71.39x = 106.77 × 42.43
4. Step 4: Simplify right side
   71.39x = 4,530.25
5. Step 5: Solve for x
   x = 4,530.25/71.39
6. Step 6: Final answer
   x = 63.46