Finding the Fourth Proportional to 89.04, 122.72 and 72.72

Step by Step Solution

1. Step 1: Write the proportion equation
   89.04 : 122.72 = 72.72 : x
2. Step 2: Convert to fraction form
   89.04/122.72 = 72.72/x
3. Step 3: Cross multiply
   89.04x = 122.72 × 72.72
4. Step 4: Simplify right side
   89.04x = 8,924.20
5. Step 5: Solve for x
   x = 8,924.20/89.04
6. Step 6: Final answer
   x = 100.23