Finding the Fourth Proportional to 80.84, 111.54 and 64.50

Step by Step Solution

1. Step 1: Write the proportion equation
   80.84 : 111.54 = 64.50 : x
2. Step 2: Convert to fraction form
   80.84/111.54 = 64.50/x
3. Step 3: Cross multiply
   80.84x = 111.54 × 64.50
4. Step 4: Simplify right side
   80.84x = 7,194.33
5. Step 5: Solve for x
   x = 7,194.33/80.84
6. Step 6: Final answer
   x = 88.99