Finding the Fourth Proportional to 2,074.97, 3,112.59 and 688.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,074.97 : 3,112.59 = 688.40 : x
2. Step 2: Convert to fraction form
   2,074.97/3,112.59 = 688.40/x
3. Step 3: Cross multiply
   2,074.97x = 3,112.59 × 688.40
4. Step 4: Simplify right side
   2,074.97x = 2,142,706.96
5. Step 5: Solve for x
   x = 2,142,706.96/2,074.97
6. Step 6: Final answer
   x = 1,032.64