Finding the Fourth Proportional to 72.65, 108.98 and 42.17

Step by Step Solution

1. Step 1: Write the proportion equation
   72.65 : 108.98 = 42.17 : x
2. Step 2: Convert to fraction form
   72.65/108.98 = 42.17/x
3. Step 3: Cross multiply
   72.65x = 108.98 × 42.17
4. Step 4: Simplify right side
   72.65x = 4,595.25
5. Step 5: Solve for x
   x = 4,595.25/72.65
6. Step 6: Final answer
   x = 63.25