Finding the Fourth Proportional to 116.29, 160.13 and 100.72

Step by Step Solution

1. Step 1: Write the proportion equation
   116.29 : 160.13 = 100.72 : x
2. Step 2: Convert to fraction form
   116.29/160.13 = 100.72/x
3. Step 3: Cross multiply
   116.29x = 160.13 × 100.72
4. Step 4: Simplify right side
   116.29x = 16,128.15
5. Step 5: Solve for x
   x = 16,128.15/116.29
6. Step 6: Final answer
   x = 138.69