Finding the Fourth Proportional to 2,109.84, 3,161.34 and 1,285.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.84 : 3,161.34 = 1,285.61 : x
2. Step 2: Convert to fraction form
   2,109.84/3,161.34 = 1,285.61/x
3. Step 3: Cross multiply
   2,109.84x = 3,161.34 × 1,285.61
4. Step 4: Simplify right side
   2,109.84x = 4,064,258.22
5. Step 5: Solve for x
   x = 4,064,258.22/2,109.84
6. Step 6: Final answer
   x = 1,926.33