Finding the Fourth Proportional to 85.89, 128.88 and 79.01

Step by Step Solution

1. Step 1: Write the proportion equation
   85.89 : 128.88 = 79.01 : x
2. Step 2: Convert to fraction form
   85.89/128.88 = 79.01/x
3. Step 3: Cross multiply
   85.89x = 128.88 × 79.01
4. Step 4: Simplify right side
   85.89x = 10,182.16
5. Step 5: Solve for x
   x = 10,182.16/85.89
6. Step 6: Final answer
   x = 118.55