Finding the Fourth Proportional to 89.89, 123.94 and 79.63

Step by Step Solution

1. Step 1: Write the proportion equation
   89.89 : 123.94 = 79.63 : x
2. Step 2: Convert to fraction form
   89.89/123.94 = 79.63/x
3. Step 3: Cross multiply
   89.89x = 123.94 × 79.63
4. Step 4: Simplify right side
   89.89x = 9,869.34
5. Step 5: Solve for x
   x = 9,869.34/89.89
6. Step 6: Final answer
   x = 109.79