Finding the Fourth Proportional to 2,109.81, 3,164.35 and 876.89

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.81 : 3,164.35 = 876.89 : x
2. Step 2: Convert to fraction form
   2,109.81/3,164.35 = 876.89/x
3. Step 3: Cross multiply
   2,109.81x = 3,164.35 × 876.89
4. Step 4: Simplify right side
   2,109.81x = 2,774,784.58
5. Step 5: Solve for x
   x = 2,774,784.58/2,109.81
6. Step 6: Final answer
   x = 1,315.18