Finding the Fourth Proportional to 11.01, 16.61 and 10.61

Step by Step Solution

1. Step 1: Write the proportion equation
   11.01 : 16.61 = 10.61 : x
2. Step 2: Convert to fraction form
   11.01/16.61 = 10.61/x
3. Step 3: Cross multiply
   11.01x = 16.61 × 10.61
4. Step 4: Simplify right side
   11.01x = 176.10
5. Step 5: Solve for x
   x = 176.10/11.01
6. Step 6: Final answer
   x = 15.99