Finding the Fourth Proportional to 2,088.67, 3,128.76 and 989.71

Step by Step Solution

1. Step 1: Write the proportion equation
   2,088.67 : 3,128.76 = 989.71 : x
2. Step 2: Convert to fraction form
   2,088.67/3,128.76 = 989.71/x
3. Step 3: Cross multiply
   2,088.67x = 3,128.76 × 989.71
4. Step 4: Simplify right side
   2,088.67x = 3,096,565.06
5. Step 5: Solve for x
   x = 3,096,565.06/2,088.67
6. Step 6: Final answer
   x = 1,482.55