Finding the Fourth Proportional to 100.69, 139.17 and 88.95

Step by Step Solution

1. Step 1: Write the proportion equation
   100.69 : 139.17 = 88.95 : x
2. Step 2: Convert to fraction form
   100.69/139.17 = 88.95/x
3. Step 3: Cross multiply
   100.69x = 139.17 × 88.95
4. Step 4: Simplify right side
   100.69x = 12,379.17
5. Step 5: Solve for x
   x = 12,379.17/100.69
6. Step 6: Final answer
   x = 122.94