Finding the Fourth Proportional to 89.39, 123.37 and 61.81

Step by Step Solution

1. Step 1: Write the proportion equation
   89.39 : 123.37 = 61.81 : x
2. Step 2: Convert to fraction form
   89.39/123.37 = 61.81/x
3. Step 3: Cross multiply
   89.39x = 123.37 × 61.81
4. Step 4: Simplify right side
   89.39x = 7,625.50
5. Step 5: Solve for x
   x = 7,625.50/89.39
6. Step 6: Final answer
   x = 85.31