Finding the Fourth Proportional to 2,100.72, 2,900.28 and 1,393.18

Step by Step Solution

1. Step 1: Write the proportion equation
   2,100.72 : 2,900.28 = 1,393.18 : x
2. Step 2: Convert to fraction form
   2,100.72/2,900.28 = 1,393.18/x
3. Step 3: Cross multiply
   2,100.72x = 2,900.28 × 1,393.18
4. Step 4: Simplify right side
   2,100.72x = 4,040,612.09
5. Step 5: Solve for x
   x = 4,040,612.09/2,100.72
6. Step 6: Final answer
   x = 1,923.44