Finding the Fourth Proportional to 28.58, 42.55 and 28.22

Step by Step Solution

1. Step 1: Write the proportion equation
   28.58 : 42.55 = 28.22 : x
2. Step 2: Convert to fraction form
   28.58/42.55 = 28.22/x
3. Step 3: Cross multiply
   28.58x = 42.55 × 28.22
4. Step 4: Simplify right side
   28.58x = 1,200.76
5. Step 5: Solve for x
   x = 1,200.76/28.58
6. Step 6: Final answer
   x = 42.01