Finding the Fourth Proportional to 1,369.68, 1,890.78 and 872.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.68 : 1,890.78 = 872.99 : x
2. Step 2: Convert to fraction form
   1,369.68/1,890.78 = 872.99/x
3. Step 3: Cross multiply
   1,369.68x = 1,890.78 × 872.99
4. Step 4: Simplify right side
   1,369.68x = 1,650,632.03
5. Step 5: Solve for x
   x = 1,650,632.03/1,369.68
6. Step 6: Final answer
   x = 1,205.12