Finding the Fourth Proportional to 2,176.71, 3,002.58 and 1,391.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,176.71 : 3,002.58 = 1,391.15 : x
2. Step 2: Convert to fraction form
   2,176.71/3,002.58 = 1,391.15/x
3. Step 3: Cross multiply
   2,176.71x = 3,002.58 × 1,391.15
4. Step 4: Simplify right side
   2,176.71x = 4,177,024.15
5. Step 5: Solve for x
   x = 4,177,024.15/2,176.71
6. Step 6: Final answer
   x = 1,918.96