Finding the Fourth Proportional to 1,399.77, 1,930.86 and 874.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.77 : 1,930.86 = 874.89 : x
2. Step 2: Convert to fraction form
   1,399.77/1,930.86 = 874.89/x
3. Step 3: Cross multiply
   1,399.77x = 1,930.86 × 874.89
4. Step 4: Simplify right side
   1,399.77x = 1,689,290.11
5. Step 5: Solve for x
   x = 1,689,290.11/1,399.77
6. Step 6: Final answer
   x = 1,206.83