Finding the Fourth Proportional to 89.21, 123.05 and 87.59

Step by Step Solution

1. Step 1: Write the proportion equation
   89.21 : 123.05 = 87.59 : x
2. Step 2: Convert to fraction form
   89.21/123.05 = 87.59/x
3. Step 3: Cross multiply
   89.21x = 123.05 × 87.59
4. Step 4: Simplify right side
   89.21x = 10,778.48
5. Step 5: Solve for x
   x = 10,778.48/89.21
6. Step 6: Final answer
   x = 120.82