Finding the Fourth Proportional to 2,656.72, 3,985.40 and 877.84

Step by Step Solution

1. Step 1: Write the proportion equation
   2,656.72 : 3,985.40 = 877.84 : x
2. Step 2: Convert to fraction form
   2,656.72/3,985.40 = 877.84/x
3. Step 3: Cross multiply
   2,656.72x = 3,985.40 × 877.84
4. Step 4: Simplify right side
   2,656.72x = 3,498,543.54
5. Step 5: Solve for x
   x = 3,498,543.54/2,656.72
6. Step 6: Final answer
   x = 1,316.87