Finding the Fourth Proportional to 3,870.36, 5,807.16 and 1,271.88

Step by Step Solution

1. Step 1: Write the proportion equation
   3,870.36 : 5,807.16 = 1,271.88 : x
2. Step 2: Convert to fraction form
   3,870.36/5,807.16 = 1,271.88/x
3. Step 3: Cross multiply
   3,870.36x = 5,807.16 × 1,271.88
4. Step 4: Simplify right side
   3,870.36x = 7,386,010.66
5. Step 5: Solve for x
   x = 7,386,010.66/3,870.36
6. Step 6: Final answer
   x = 1,908.35