Finding the Fourth Proportional to 2,118.15, 2,921.15 and 1,371.33

Step by Step Solution

1. Step 1: Write the proportion equation
   2,118.15 : 2,921.15 = 1,371.33 : x
2. Step 2: Convert to fraction form
   2,118.15/2,921.15 = 1,371.33/x
3. Step 3: Cross multiply
   2,118.15x = 2,921.15 × 1,371.33
4. Step 4: Simplify right side
   2,118.15x = 4,005,853.77
5. Step 5: Solve for x
   x = 4,005,853.77/2,118.15
6. Step 6: Final answer
   x = 1,891.20