Finding the Fourth Proportional to 42.88, 64.01 and 38.06

Step by Step Solution

1. Step 1: Write the proportion equation
   42.88 : 64.01 = 38.06 : x
2. Step 2: Convert to fraction form
   42.88/64.01 = 38.06/x
3. Step 3: Cross multiply
   42.88x = 64.01 × 38.06
4. Step 4: Simplify right side
   42.88x = 2,436.22
5. Step 5: Solve for x
   x = 2,436.22/42.88
6. Step 6: Final answer
   x = 56.81