Finding the Fourth Proportional to 3,870.80, 5,806.89 and 1,409.07

Step by Step Solution

1. Step 1: Write the proportion equation
   3,870.80 : 5,806.89 = 1,409.07 : x
2. Step 2: Convert to fraction form
   3,870.80/5,806.89 = 1,409.07/x
3. Step 3: Cross multiply
   3,870.80x = 5,806.89 × 1,409.07
4. Step 4: Simplify right side
   3,870.80x = 8,182,314.49
5. Step 5: Solve for x
   x = 8,182,314.49/3,870.80
6. Step 6: Final answer
   x = 2,113.86