Finding the Fourth Proportional to 89.87, 134.49 and 78.96

Step by Step Solution

1. Step 1: Write the proportion equation
   89.87 : 134.49 = 78.96 : x
2. Step 2: Convert to fraction form
   89.87/134.49 = 78.96/x
3. Step 3: Cross multiply
   89.87x = 134.49 × 78.96
4. Step 4: Simplify right side
   89.87x = 10,619.33
5. Step 5: Solve for x
   x = 10,619.33/89.87
6. Step 6: Final answer
   x = 118.17