Finding the Fourth Proportional to 71.59, 107.46 and 42.70

Step by Step Solution

1. Step 1: Write the proportion equation
   71.59 : 107.46 = 42.70 : x
2. Step 2: Convert to fraction form
   71.59/107.46 = 42.70/x
3. Step 3: Cross multiply
   71.59x = 107.46 × 42.70
4. Step 4: Simplify right side
   71.59x = 4,588.54
5. Step 5: Solve for x
   x = 4,588.54/71.59
6. Step 6: Final answer
   x = 64.09