Finding the Fourth Proportional to 89.01, 132.89 and 78.65

Step by Step Solution

1. Step 1: Write the proportion equation
   89.01 : 132.89 = 78.65 : x
2. Step 2: Convert to fraction form
   89.01/132.89 = 78.65/x
3. Step 3: Cross multiply
   89.01x = 132.89 × 78.65
4. Step 4: Simplify right side
   89.01x = 10,451.80
5. Step 5: Solve for x
   x = 10,451.80/89.01
6. Step 6: Final answer
   x = 117.42