Finding the Fourth Proportional to 1,488.72, 2,054.24 and 859.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,488.72 : 2,054.24 = 859.20 : x
2. Step 2: Convert to fraction form
   1,488.72/2,054.24 = 859.20/x
3. Step 3: Cross multiply
   1,488.72x = 2,054.24 × 859.20
4. Step 4: Simplify right side
   1,488.72x = 1,765,003.01
5. Step 5: Solve for x
   x = 1,765,003.01/1,488.72
6. Step 6: Final answer
   x = 1,185.58