Finding the Fourth Proportional to 1,054.06, 1,578.25 and 989.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,054.06 : 1,578.25 = 989.12 : x
2. Step 2: Convert to fraction form
   1,054.06/1,578.25 = 989.12/x
3. Step 3: Cross multiply
   1,054.06x = 1,578.25 × 989.12
4. Step 4: Simplify right side
   1,054.06x = 1,561,073.69
5. Step 5: Solve for x
   x = 1,561,073.69/1,054.06
6. Step 6: Final answer
   x = 1,481.02