Finding the Fourth Proportional to 1,449.12, 1,998.72 and 859.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,449.12 : 1,998.72 = 859.20 : x
2. Step 2: Convert to fraction form
   1,449.12/1,998.72 = 859.20/x
3. Step 3: Cross multiply
   1,449.12x = 1,998.72 × 859.20
4. Step 4: Simplify right side
   1,449.12x = 1,717,300.22
5. Step 5: Solve for x
   x = 1,717,300.22/1,449.12
6. Step 6: Final answer
   x = 1,185.06