Finding the Fourth Proportional to 90.18, 135.22 and 42.06

Step by Step Solution

1. Step 1: Write the proportion equation
   90.18 : 135.22 = 42.06 : x
2. Step 2: Convert to fraction form
   90.18/135.22 = 42.06/x
3. Step 3: Cross multiply
   90.18x = 135.22 × 42.06
4. Step 4: Simplify right side
   90.18x = 5,687.35
5. Step 5: Solve for x
   x = 5,687.35/90.18
6. Step 6: Final answer
   x = 63.07