Finding the Fourth Proportional to 89.83, 123.87 and 77.42

Step by Step Solution

1. Step 1: Write the proportion equation
   89.83 : 123.87 = 77.42 : x
2. Step 2: Convert to fraction form
   89.83/123.87 = 77.42/x
3. Step 3: Cross multiply
   89.83x = 123.87 × 77.42
4. Step 4: Simplify right side
   89.83x = 9,590.02
5. Step 5: Solve for x
   x = 9,590.02/89.83
6. Step 6: Final answer
   x = 106.76