Finding the Fourth Proportional to 72.51, 108.74 and 42.09

Step by Step Solution

1. Step 1: Write the proportion equation
   72.51 : 108.74 = 42.09 : x
2. Step 2: Convert to fraction form
   72.51/108.74 = 42.09/x
3. Step 3: Cross multiply
   72.51x = 108.74 × 42.09
4. Step 4: Simplify right side
   72.51x = 4,576.53
5. Step 5: Solve for x
   x = 4,576.53/72.51
6. Step 6: Final answer
   x = 63.11