Finding the Fourth Proportional to 1,908.60, 2,864.83 and 1,321.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,908.60 : 2,864.83 = 1,321.57 : x
2. Step 2: Convert to fraction form
   1,908.60/2,864.83 = 1,321.57/x
3. Step 3: Cross multiply
   1,908.60x = 2,864.83 × 1,321.57
4. Step 4: Simplify right side
   1,908.60x = 3,786,066.76
5. Step 5: Solve for x
   x = 3,786,066.76/1,908.60
6. Step 6: Final answer
   x = 1,983.69