Finding the Fourth Proportional to 21,017.81, 31,531.71 and 7,166.81

Step by Step Solution

1. Step 1: Write the proportion equation
   21,017.81 : 31,531.71 = 7,166.81 : x
2. Step 2: Convert to fraction form
   21,017.81/31,531.71 = 7,166.81/x
3. Step 3: Cross multiply
   21,017.81x = 31,531.71 × 7,166.81
4. Step 4: Simplify right side
   21,017.81x = 225,981,880.25
5. Step 5: Solve for x
   x = 225,981,880.25/21,017.81
6. Step 6: Final answer
   x = 10,751.92