Finding the Fourth Proportional to 91.96, 137.52 and 78.59

Step by Step Solution

1. Step 1: Write the proportion equation
   91.96 : 137.52 = 78.59 : x
2. Step 2: Convert to fraction form
   91.96/137.52 = 78.59/x
3. Step 3: Cross multiply
   91.96x = 137.52 × 78.59
4. Step 4: Simplify right side
   91.96x = 10,807.70
5. Step 5: Solve for x
   x = 10,807.70/91.96
6. Step 6: Final answer
   x = 117.53