Finding the Fourth Proportional to 89.55, 123.62 and 85.10

Step by Step Solution

1. Step 1: Write the proportion equation
   89.55 : 123.62 = 85.10 : x
2. Step 2: Convert to fraction form
   89.55/123.62 = 85.10/x
3. Step 3: Cross multiply
   89.55x = 123.62 × 85.10
4. Step 4: Simplify right side
   89.55x = 10,519.02
5. Step 5: Solve for x
   x = 10,519.02/89.55
6. Step 6: Final answer
   x = 117.47