Finding the Fourth Proportional to 90.48, 135.72 and 42.42

Step by Step Solution

1. Step 1: Write the proportion equation
   90.48 : 135.72 = 42.42 : x
2. Step 2: Convert to fraction form
   90.48/135.72 = 42.42/x
3. Step 3: Cross multiply
   90.48x = 135.72 × 42.42
4. Step 4: Simplify right side
   90.48x = 5,757.24
5. Step 5: Solve for x
   x = 5,757.24/90.48
6. Step 6: Final answer
   x = 63.63