Finding the Fourth Proportional to 116.30, 160.56 and 100.72

Step by Step Solution

1. Step 1: Write the proportion equation
   116.30 : 160.56 = 100.72 : x
2. Step 2: Convert to fraction form
   116.30/160.56 = 100.72/x
3. Step 3: Cross multiply
   116.30x = 160.56 × 100.72
4. Step 4: Simplify right side
   116.30x = 16,171.07
5. Step 5: Solve for x
   x = 16,171.07/116.30
6. Step 6: Final answer
   x = 139.05