Finding the Fourth Proportional to 89.42, 123.41 and 78.54

Step by Step Solution

1. Step 1: Write the proportion equation
   89.42 : 123.41 = 78.54 : x
2. Step 2: Convert to fraction form
   89.42/123.41 = 78.54/x
3. Step 3: Cross multiply
   89.42x = 123.41 × 78.54
4. Step 4: Simplify right side
   89.42x = 9,692.62
5. Step 5: Solve for x
   x = 9,692.62/89.42
6. Step 6: Final answer
   x = 108.39