Finding the Fourth Proportional to 2,877.72, 3,969.91 and 1,815

Step by Step Solution

1. Step 1: Write the proportion equation
   2,877.72 : 3,969.91 = 1,815 : x
2. Step 2: Convert to fraction form
   2,877.72/3,969.91 = 1,815/x
3. Step 3: Cross multiply
   2,877.72x = 3,969.91 × 1,815
4. Step 4: Simplify right side
   2,877.72x = 7,205,386.65
5. Step 5: Solve for x
   x = 7,205,386.65/2,877.72
6. Step 6: Final answer
   x = 2,503.85