Finding the Fourth Proportional to 108.56, 149.83 and 64.89

Step by Step Solution

1. Step 1: Write the proportion equation
   108.56 : 149.83 = 64.89 : x
2. Step 2: Convert to fraction form
   108.56/149.83 = 64.89/x
3. Step 3: Cross multiply
   108.56x = 149.83 × 64.89
4. Step 4: Simplify right side
   108.56x = 9,722.31
5. Step 5: Solve for x
   x = 9,722.31/108.56
6. Step 6: Final answer
   x = 89.55