Finding the Fourth Proportional to 111.26, 153.59 and 78.59

Step by Step Solution

1. Step 1: Write the proportion equation
   111.26 : 153.59 = 78.59 : x
2. Step 2: Convert to fraction form
   111.26/153.59 = 78.59/x
3. Step 3: Cross multiply
   111.26x = 153.59 × 78.59
4. Step 4: Simplify right side
   111.26x = 12,069.48
5. Step 5: Solve for x
   x = 12,069.48/111.26
6. Step 6: Final answer
   x = 108.48