Finding the Fourth Proportional to 105.51, 158.34 and 82.56

Step by Step Solution

1. Step 1: Write the proportion equation
   105.51 : 158.34 = 82.56 : x
2. Step 2: Convert to fraction form
   105.51/158.34 = 82.56/x
3. Step 3: Cross multiply
   105.51x = 158.34 × 82.56
4. Step 4: Simplify right side
   105.51x = 13,072.55
5. Step 5: Solve for x
   x = 13,072.55/105.51
6. Step 6: Final answer
   x = 123.90