Finding the Fourth Proportional to 89.58, 123.43 and 83.50

Step by Step Solution

1. Step 1: Write the proportion equation
   89.58 : 123.43 = 83.50 : x
2. Step 2: Convert to fraction form
   89.58/123.43 = 83.50/x
3. Step 3: Cross multiply
   89.58x = 123.43 × 83.50
4. Step 4: Simplify right side
   89.58x = 10,306.41
5. Step 5: Solve for x
   x = 10,306.41/89.58
6. Step 6: Final answer
   x = 115.05