Finding the Fourth Proportional to 105.78, 146.06 and 83.62

Step by Step Solution

1. Step 1: Write the proportion equation
   105.78 : 146.06 = 83.62 : x
2. Step 2: Convert to fraction form
   105.78/146.06 = 83.62/x
3. Step 3: Cross multiply
   105.78x = 146.06 × 83.62
4. Step 4: Simplify right side
   105.78x = 12,213.54
5. Step 5: Solve for x
   x = 12,213.54/105.78
6. Step 6: Final answer
   x = 115.46