Finding the Fourth Proportional to 72.87, 109.22 and 42.47

Step by Step Solution

1. Step 1: Write the proportion equation
   72.87 : 109.22 = 42.47 : x
2. Step 2: Convert to fraction form
   72.87/109.22 = 42.47/x
3. Step 3: Cross multiply
   72.87x = 109.22 × 42.47
4. Step 4: Simplify right side
   72.87x = 4,637.81
5. Step 5: Solve for x
   x = 4,637.81/72.87
6. Step 6: Final answer
   x = 63.65