Finding the Fourth Proportional to 111.83, 154.34 and 65.21

Step by Step Solution

1. Step 1: Write the proportion equation
   111.83 : 154.34 = 65.21 : x
2. Step 2: Convert to fraction form
   111.83/154.34 = 65.21/x
3. Step 3: Cross multiply
   111.83x = 154.34 × 65.21
4. Step 4: Simplify right side
   111.83x = 10,063.41
5. Step 5: Solve for x
   x = 10,063.41/111.83
6. Step 6: Final answer
   x = 89.99