Finding the Fourth Proportional to 2,720.76, 4,081.86 and 989.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,720.76 : 4,081.86 = 989.56 : x
2. Step 2: Convert to fraction form
   2,720.76/4,081.86 = 989.56/x
3. Step 3: Cross multiply
   2,720.76x = 4,081.86 × 989.56
4. Step 4: Simplify right side
   2,720.76x = 4,039,245.38
5. Step 5: Solve for x
   x = 4,039,245.38/2,720.76
6. Step 6: Final answer
   x = 1,484.60