Finding the Fourth Proportional to 90.58, 135.72 and 55.82

Step by Step Solution

1. Step 1: Write the proportion equation
   90.58 : 135.72 = 55.82 : x
2. Step 2: Convert to fraction form
   90.58/135.72 = 55.82/x
3. Step 3: Cross multiply
   90.58x = 135.72 × 55.82
4. Step 4: Simplify right side
   90.58x = 7,575.89
5. Step 5: Solve for x
   x = 7,575.89/90.58
6. Step 6: Final answer
   x = 83.64