Finding the Fourth Proportional to 3,687.99, 5,088.86 and 2,115.78

Step by Step Solution

1. Step 1: Write the proportion equation
   3,687.99 : 5,088.86 = 2,115.78 : x
2. Step 2: Convert to fraction form
   3,687.99/5,088.86 = 2,115.78/x
3. Step 3: Cross multiply
   3,687.99x = 5,088.86 × 2,115.78
4. Step 4: Simplify right side
   3,687.99x = 10,766,897.63
5. Step 5: Solve for x
   x = 10,766,897.63/3,687.99
6. Step 6: Final answer
   x = 2,919.45