Finding the Fourth Proportional to 116.39, 160.56 and 90.17

Step by Step Solution

1. Step 1: Write the proportion equation
   116.39 : 160.56 = 90.17 : x
2. Step 2: Convert to fraction form
   116.39/160.56 = 90.17/x
3. Step 3: Cross multiply
   116.39x = 160.56 × 90.17
4. Step 4: Simplify right side
   116.39x = 14,476.89
5. Step 5: Solve for x
   x = 14,476.89/116.39
6. Step 6: Final answer
   x = 124.39