Finding the Fourth Proportional to 72.50, 108.79 and 42.07

Step by Step Solution

1. Step 1: Write the proportion equation
   72.50 : 108.79 = 42.07 : x
2. Step 2: Convert to fraction form
   72.50/108.79 = 42.07/x
3. Step 3: Cross multiply
   72.50x = 108.79 × 42.07
4. Step 4: Simplify right side
   72.50x = 4,576.86
5. Step 5: Solve for x
   x = 4,576.86/72.50
6. Step 6: Final answer
   x = 63.13