Finding the Fourth Proportional to 1,805.78, 2,486.42 and 1,539.63

Step by Step Solution

1. Step 1: Write the proportion equation
   1,805.78 : 2,486.42 = 1,539.63 : x
2. Step 2: Convert to fraction form
   1,805.78/2,486.42 = 1,539.63/x
3. Step 3: Cross multiply
   1,805.78x = 2,486.42 × 1,539.63
4. Step 4: Simplify right side
   1,805.78x = 3,828,146.69
5. Step 5: Solve for x
   x = 3,828,146.69/1,805.78
6. Step 6: Final answer
   x = 2,119.95