Finding the Fourth Proportional to 2,007.20, 2,772.69 and 1,820.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,007.20 : 2,772.69 = 1,820.90 : x
2. Step 2: Convert to fraction form
   2,007.20/2,772.69 = 1,820.90/x
3. Step 3: Cross multiply
   2,007.20x = 2,772.69 × 1,820.90
4. Step 4: Simplify right side
   2,007.20x = 5,048,791.22
5. Step 5: Solve for x
   x = 5,048,791.22/2,007.20
6. Step 6: Final answer
   x = 2,515.34