Finding the Fourth Proportional to 2,109.62, 3,164.68 and 877.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,109.62 : 3,164.68 = 877.86 : x
2. Step 2: Convert to fraction form
   2,109.62/3,164.68 = 877.86/x
3. Step 3: Cross multiply
   2,109.62x = 3,164.68 × 877.86
4. Step 4: Simplify right side
   2,109.62x = 2,778,143.79
5. Step 5: Solve for x
   x = 2,778,143.79/2,109.62
6. Step 6: Final answer
   x = 1,316.90