Finding the Fourth Proportional to 42.47, 63.69 and 28.05

Step by Step Solution

1. Step 1: Write the proportion equation
   42.47 : 63.69 = 28.05 : x
2. Step 2: Convert to fraction form
   42.47/63.69 = 28.05/x
3. Step 3: Cross multiply
   42.47x = 63.69 × 28.05
4. Step 4: Simplify right side
   42.47x = 1,786.50
5. Step 5: Solve for x
   x = 1,786.50/42.47
6. Step 6: Final answer
   x = 42.07