Finding the Fourth Proportional to 2,091.59, 2,884.05 and 1,428.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,091.59 : 2,884.05 = 1,428.80 : x
2. Step 2: Convert to fraction form
   2,091.59/2,884.05 = 1,428.80/x
3. Step 3: Cross multiply
   2,091.59x = 2,884.05 × 1,428.80
4. Step 4: Simplify right side
   2,091.59x = 4,120,730.64
5. Step 5: Solve for x
   x = 4,120,730.64/2,091.59
6. Step 6: Final answer
   x = 1,970.14