Finding the Fourth Proportional to 111.28, 153.33 and 100.19

Step by Step Solution

1. Step 1: Write the proportion equation
   111.28 : 153.33 = 100.19 : x
2. Step 2: Convert to fraction form
   111.28/153.33 = 100.19/x
3. Step 3: Cross multiply
   111.28x = 153.33 × 100.19
4. Step 4: Simplify right side
   111.28x = 15,362.56
5. Step 5: Solve for x
   x = 15,362.56/111.28
6. Step 6: Final answer
   x = 138.06