Finding the Fourth Proportional to 90.31, 135.57 and 42.32

Step by Step Solution

1. Step 1: Write the proportion equation
   90.31 : 135.57 = 42.32 : x
2. Step 2: Convert to fraction form
   90.31/135.57 = 42.32/x
3. Step 3: Cross multiply
   90.31x = 135.57 × 42.32
4. Step 4: Simplify right side
   90.31x = 5,737.32
5. Step 5: Solve for x
   x = 5,737.32/90.31
6. Step 6: Final answer
   x = 63.53