Finding the Fourth Proportional to 42.71, 64.06 and 18.67

Step by Step Solution

1. Step 1: Write the proportion equation
   42.71 : 64.06 = 18.67 : x
2. Step 2: Convert to fraction form
   42.71/64.06 = 18.67/x
3. Step 3: Cross multiply
   42.71x = 64.06 × 18.67
4. Step 4: Simplify right side
   42.71x = 1,196.00
5. Step 5: Solve for x
   x = 1,196.00/42.71
6. Step 6: Final answer
   x = 28.00