Finding the Fourth Proportional to 72.96, 109.42 and 42.56

Step by Step Solution

1. Step 1: Write the proportion equation
   72.96 : 109.42 = 42.56 : x
2. Step 2: Convert to fraction form
   72.96/109.42 = 42.56/x
3. Step 3: Cross multiply
   72.96x = 109.42 × 42.56
4. Step 4: Simplify right side
   72.96x = 4,656.92
5. Step 5: Solve for x
   x = 4,656.92/72.96
6. Step 6: Final answer
   x = 63.83