Finding the Fourth Proportional to 111.78, 153.23 and 109.89

Step by Step Solution

1. Step 1: Write the proportion equation
   111.78 : 153.23 = 109.89 : x
2. Step 2: Convert to fraction form
   111.78/153.23 = 109.89/x
3. Step 3: Cross multiply
   111.78x = 153.23 × 109.89
4. Step 4: Simplify right side
   111.78x = 16,837.90
5. Step 5: Solve for x
   x = 16,837.90/111.78
6. Step 6: Final answer
   x = 150.63