Finding the Fourth Proportional to 2,035.21, 2,807.55 and 1,287.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,035.21 : 2,807.55 = 1,287.91 : x
2. Step 2: Convert to fraction form
   2,035.21/2,807.55 = 1,287.91/x
3. Step 3: Cross multiply
   2,035.21x = 2,807.55 × 1,287.91
4. Step 4: Simplify right side
   2,035.21x = 3,615,871.72
5. Step 5: Solve for x
   x = 3,615,871.72/2,035.21
6. Step 6: Final answer
   x = 1,776.66