Finding the Fourth Proportional to 2,661.76, 3,989.91 and 1,017.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,661.76 : 3,989.91 = 1,017.87 : x
2. Step 2: Convert to fraction form
   2,661.76/3,989.91 = 1,017.87/x
3. Step 3: Cross multiply
   2,661.76x = 3,989.91 × 1,017.87
4. Step 4: Simplify right side
   2,661.76x = 4,061,209.69
5. Step 5: Solve for x
   x = 4,061,209.69/2,661.76
6. Step 6: Final answer
   x = 1,525.76