Finding the Fourth Proportional to 2,860.83, 4,290.17 and 1,320.75

Step by Step Solution

1. Step 1: Write the proportion equation
   2,860.83 : 4,290.17 = 1,320.75 : x
2. Step 2: Convert to fraction form
   2,860.83/4,290.17 = 1,320.75/x
3. Step 3: Cross multiply
   2,860.83x = 4,290.17 × 1,320.75
4. Step 4: Simplify right side
   2,860.83x = 5,666,235.42
5. Step 5: Solve for x
   x = 5,666,235.42/2,860.83
6. Step 6: Final answer
   x = 1,980.63