Finding the Fourth Proportional to 105.62, 158.34 and 78.53

Step by Step Solution

1. Step 1: Write the proportion equation
   105.62 : 158.34 = 78.53 : x
2. Step 2: Convert to fraction form
   105.62/158.34 = 78.53/x
3. Step 3: Cross multiply
   105.62x = 158.34 × 78.53
4. Step 4: Simplify right side
   105.62x = 12,434.44
5. Step 5: Solve for x
   x = 12,434.44/105.62
6. Step 6: Final answer
   x = 117.73