Finding the Fourth Proportional to 2,085.66, 3,128.31 and 1,263.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.66 : 3,128.31 = 1,263.69 : x
2. Step 2: Convert to fraction form
   2,085.66/3,128.31 = 1,263.69/x
3. Step 3: Cross multiply
   2,085.66x = 3,128.31 × 1,263.69
4. Step 4: Simplify right side
   2,085.66x = 3,953,214.06
5. Step 5: Solve for x
   x = 3,953,214.06/2,085.66
6. Step 6: Final answer
   x = 1,895.43