Finding the Fourth Proportional to 71.02, 106.37 and 42.15

Step by Step Solution

1. Step 1: Write the proportion equation
   71.02 : 106.37 = 42.15 : x
2. Step 2: Convert to fraction form
   71.02/106.37 = 42.15/x
3. Step 3: Cross multiply
   71.02x = 106.37 × 42.15
4. Step 4: Simplify right side
   71.02x = 4,483.28
5. Step 5: Solve for x
   x = 4,483.28/71.02
6. Step 6: Final answer
   x = 63.13