Finding the Fourth Proportional to 1,680.99, 2,523.83 and 859.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,680.99 : 2,523.83 = 859.83 : x
2. Step 2: Convert to fraction form
   1,680.99/2,523.83 = 859.83/x
3. Step 3: Cross multiply
   1,680.99x = 2,523.83 × 859.83
4. Step 4: Simplify right side
   1,680.99x = 2,170,060.45
5. Step 5: Solve for x
   x = 2,170,060.45/1,680.99
6. Step 6: Final answer
   x = 1,290.94