Finding the Fourth Proportional to 116.78, 173.75 and 111.78

Step by Step Solution

1. Step 1: Write the proportion equation
   116.78 : 173.75 = 111.78 : x
2. Step 2: Convert to fraction form
   116.78/173.75 = 111.78/x
3. Step 3: Cross multiply
   116.78x = 173.75 × 111.78
4. Step 4: Simplify right side
   116.78x = 19,421.22
5. Step 5: Solve for x
   x = 19,421.22/116.78
6. Step 6: Final answer
   x = 166.31