Finding the Fourth Proportional to 2,105.90, 2,907.31 and 1,266.81

Step by Step Solution

1. Step 1: Write the proportion equation
   2,105.90 : 2,907.31 = 1,266.81 : x
2. Step 2: Convert to fraction form
   2,105.90/2,907.31 = 1,266.81/x
3. Step 3: Cross multiply
   2,105.90x = 2,907.31 × 1,266.81
4. Step 4: Simplify right side
   2,105.90x = 3,683,009.38
5. Step 5: Solve for x
   x = 3,683,009.38/2,105.90
6. Step 6: Final answer
   x = 1,748.90