Finding the Fourth Proportional to 89.00, 122.83 and 85.10

Step by Step Solution

1. Step 1: Write the proportion equation
   89.00 : 122.83 = 85.10 : x
2. Step 2: Convert to fraction form
   89.00/122.83 = 85.10/x
3. Step 3: Cross multiply
   89.00x = 122.83 × 85.10
4. Step 4: Simplify right side
   89.00x = 10,452.83
5. Step 5: Solve for x
   x = 10,452.83/89.00
6. Step 6: Final answer
   x = 117.45