Finding the Fourth Proportional to 90.96, 124.99 and 85.69

Step by Step Solution

1. Step 1: Write the proportion equation
   90.96 : 124.99 = 85.69 : x
2. Step 2: Convert to fraction form
   90.96/124.99 = 85.69/x
3. Step 3: Cross multiply
   90.96x = 124.99 × 85.69
4. Step 4: Simplify right side
   90.96x = 10,710.39
5. Step 5: Solve for x
   x = 10,710.39/90.96
6. Step 6: Final answer
   x = 117.75