Finding the Fourth Proportional to 111.61, 167.37 and 100.78

Step by Step Solution

1. Step 1: Write the proportion equation
   111.61 : 167.37 = 100.78 : x
2. Step 2: Convert to fraction form
   111.61/167.37 = 100.78/x
3. Step 3: Cross multiply
   111.61x = 167.37 × 100.78
4. Step 4: Simplify right side
   111.61x = 16,866.75
5. Step 5: Solve for x
   x = 16,866.75/111.61
6. Step 6: Final answer
   x = 151.12