Finding the Fourth Proportional to 109.74, 164.39 and 82.72

Step by Step Solution

1. Step 1: Write the proportion equation
   109.74 : 164.39 = 82.72 : x
2. Step 2: Convert to fraction form
   109.74/164.39 = 82.72/x
3. Step 3: Cross multiply
   109.74x = 164.39 × 82.72
4. Step 4: Simplify right side
   109.74x = 13,597.52
5. Step 5: Solve for x
   x = 13,597.52/109.74
6. Step 6: Final answer
   x = 123.91