Finding the Fourth Proportional to 88.79, 132.91 and 78.71

Step by Step Solution

1. Step 1: Write the proportion equation
   88.79 : 132.91 = 78.71 : x
2. Step 2: Convert to fraction form
   88.79/132.91 = 78.71/x
3. Step 3: Cross multiply
   88.79x = 132.91 × 78.71
4. Step 4: Simplify right side
   88.79x = 10,460.48
5. Step 5: Solve for x
   x = 10,460.48/88.79
6. Step 6: Final answer
   x = 117.82