Finding the Fourth Proportional to 90.39, 124.77 and 57.59

Step by Step Solution

1. Step 1: Write the proportion equation
   90.39 : 124.77 = 57.59 : x
2. Step 2: Convert to fraction form
   90.39/124.77 = 57.59/x
3. Step 3: Cross multiply
   90.39x = 124.77 × 57.59
4. Step 4: Simplify right side
   90.39x = 7,185.50
5. Step 5: Solve for x
   x = 7,185.50/90.39
6. Step 6: Final answer
   x = 79.49