Finding the Fourth Proportional to 2,818.69, 3,890.69 and 1,979.60

Step by Step Solution

1. Step 1: Write the proportion equation
   2,818.69 : 3,890.69 = 1,979.60 : x
2. Step 2: Convert to fraction form
   2,818.69/3,890.69 = 1,979.60/x
3. Step 3: Cross multiply
   2,818.69x = 3,890.69 × 1,979.60
4. Step 4: Simplify right side
   2,818.69x = 7,701,980.57
5. Step 5: Solve for x
   x = 7,701,980.57/2,818.69
6. Step 6: Final answer
   x = 2,732.47