Finding the Fourth Proportional to 1,513.55, 2,088.15 and 989.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,513.55 : 2,088.15 = 989.88 : x
2. Step 2: Convert to fraction form
   1,513.55/2,088.15 = 989.88/x
3. Step 3: Cross multiply
   1,513.55x = 2,088.15 × 989.88
4. Step 4: Simplify right side
   1,513.55x = 2,067,017.92
5. Step 5: Solve for x
   x = 2,067,017.92/1,513.55
6. Step 6: Final answer
   x = 1,365.68