Finding the Fourth Proportional to 105.98, 146.09 and 90.32

Step by Step Solution

1. Step 1: Write the proportion equation
   105.98 : 146.09 = 90.32 : x
2. Step 2: Convert to fraction form
   105.98/146.09 = 90.32/x
3. Step 3: Cross multiply
   105.98x = 146.09 × 90.32
4. Step 4: Simplify right side
   105.98x = 13,194.34
5. Step 5: Solve for x
   x = 13,194.34/105.98
6. Step 6: Final answer
   x = 124.50