Finding the Fourth Proportional to 2,037.78, 2,811.05 and 1,290.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,037.78 : 2,811.05 = 1,290.42 : x
2. Step 2: Convert to fraction form
   2,037.78/2,811.05 = 1,290.42/x
3. Step 3: Cross multiply
   2,037.78x = 2,811.05 × 1,290.42
4. Step 4: Simplify right side
   2,037.78x = 3,627,428.69
5. Step 5: Solve for x
   x = 3,627,428.69/2,037.78
6. Step 6: Final answer
   x = 1,780.09