Finding the Fourth Proportional to 2,131.97, 2,942.12 and 1,247.60

Step by Step Solution

1. Step 1: Write the proportion equation
   2,131.97 : 2,942.12 = 1,247.60 : x
2. Step 2: Convert to fraction form
   2,131.97/2,942.12 = 1,247.60/x
3. Step 3: Cross multiply
   2,131.97x = 2,942.12 × 1,247.60
4. Step 4: Simplify right side
   2,131.97x = 3,670,588.91
5. Step 5: Solve for x
   x = 3,670,588.91/2,131.97
6. Step 6: Final answer
   x = 1,721.69