Finding the Fourth Proportional to 105.98, 158.72 and 71.70

Step by Step Solution

1. Step 1: Write the proportion equation
   105.98 : 158.72 = 71.70 : x
2. Step 2: Convert to fraction form
   105.98/158.72 = 71.70/x
3. Step 3: Cross multiply
   105.98x = 158.72 × 71.70
4. Step 4: Simplify right side
   105.98x = 11,380.22
5. Step 5: Solve for x
   x = 11,380.22/105.98
6. Step 6: Final answer
   x = 107.38