Finding the Fourth Proportional to 1,586.39, 2,189.17 and 878.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,586.39 : 2,189.17 = 878.27 : x
2. Step 2: Convert to fraction form
   1,586.39/2,189.17 = 878.27/x
3. Step 3: Cross multiply
   1,586.39x = 2,189.17 × 878.27
4. Step 4: Simplify right side
   1,586.39x = 1,922,685.61
5. Step 5: Solve for x
   x = 1,922,685.61/1,586.39
6. Step 6: Final answer
   x = 1,211.99