Finding the Fourth Proportional to 1,857.54, 2,785.59 and 870.21

Step by Step Solution

1. Step 1: Write the proportion equation
   1,857.54 : 2,785.59 = 870.21 : x
2. Step 2: Convert to fraction form
   1,857.54/2,785.59 = 870.21/x
3. Step 3: Cross multiply
   1,857.54x = 2,785.59 × 870.21
4. Step 4: Simplify right side
   1,857.54x = 2,424,048.27
5. Step 5: Solve for x
   x = 2,424,048.27/1,857.54
6. Step 6: Final answer
   x = 1,304.98