Finding the Fourth Proportional to 2,806.84, 3,870.40 and 1,921.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,806.84 : 3,870.40 = 1,921.24 : x
2. Step 2: Convert to fraction form
   2,806.84/3,870.40 = 1,921.24/x
3. Step 3: Cross multiply
   2,806.84x = 3,870.40 × 1,921.24
4. Step 4: Simplify right side
   2,806.84x = 7,435,967.30
5. Step 5: Solve for x
   x = 7,435,967.30/2,806.84
6. Step 6: Final answer
   x = 2,649.23