Finding the Fourth Proportional to 89.33, 123.21 and 78.98

Step by Step Solution

1. Step 1: Write the proportion equation
   89.33 : 123.21 = 78.98 : x
2. Step 2: Convert to fraction form
   89.33/123.21 = 78.98/x
3. Step 3: Cross multiply
   89.33x = 123.21 × 78.98
4. Step 4: Simplify right side
   89.33x = 9,730.51
5. Step 5: Solve for x
   x = 9,730.51/89.33
6. Step 6: Final answer
   x = 108.93