Finding the Fourth Proportional to 111.82, 154.34 and 65.21

Step by Step Solution

1. Step 1: Write the proportion equation
   111.82 : 154.34 = 65.21 : x
2. Step 2: Convert to fraction form
   111.82/154.34 = 65.21/x
3. Step 3: Cross multiply
   111.82x = 154.34 × 65.21
4. Step 4: Simplify right side
   111.82x = 10,064.51
5. Step 5: Solve for x
   x = 10,064.51/111.82
6. Step 6: Final answer
   x = 90.01