Finding the Fourth Proportional to 90.81, 136.21 and 42.04

Step by Step Solution

1. Step 1: Write the proportion equation
   90.81 : 136.21 = 42.04 : x
2. Step 2: Convert to fraction form
   90.81/136.21 = 42.04/x
3. Step 3: Cross multiply
   90.81x = 136.21 × 42.04
4. Step 4: Simplify right side
   90.81x = 5,726.61
5. Step 5: Solve for x
   x = 5,726.61/90.81
6. Step 6: Final answer
   x = 63.06