Finding the Fourth Proportional to 2,870.67, 3,963.41 and 1,989.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,870.67 : 3,963.41 = 1,989.18 : x
2. Step 2: Convert to fraction form
   2,870.67/3,963.41 = 1,989.18/x
3. Step 3: Cross multiply
   2,870.67x = 3,963.41 × 1,989.18
4. Step 4: Simplify right side
   2,870.67x = 7,883,935.90
5. Step 5: Solve for x
   x = 7,883,935.90/2,870.67
6. Step 6: Final answer
   x = 2,746.37