Finding the Fourth Proportional to 90.38, 135.57 and 42.25

Step by Step Solution

1. Step 1: Write the proportion equation
   90.38 : 135.57 = 42.25 : x
2. Step 2: Convert to fraction form
   90.38/135.57 = 42.25/x
3. Step 3: Cross multiply
   90.38x = 135.57 × 42.25
4. Step 4: Simplify right side
   90.38x = 5,727.83
5. Step 5: Solve for x
   x = 5,727.83/90.38
6. Step 6: Final answer
   x = 63.38