Finding the Fourth Proportional to 89.45, 134.18 and 28.57

Step by Step Solution

1. Step 1: Write the proportion equation
   89.45 : 134.18 = 28.57 : x
2. Step 2: Convert to fraction form
   89.45/134.18 = 28.57/x
3. Step 3: Cross multiply
   89.45x = 134.18 × 28.57
4. Step 4: Simplify right side
   89.45x = 3,833.52
5. Step 5: Solve for x
   x = 3,833.52/89.45
6. Step 6: Final answer
   x = 42.86