Finding the Fourth Proportional to 1,681.58, 2,320.61 and 935.57

Step by Step Solution

1. Step 1: Write the proportion equation
   1,681.58 : 2,320.61 = 935.57 : x
2. Step 2: Convert to fraction form
   1,681.58/2,320.61 = 935.57/x
3. Step 3: Cross multiply
   1,681.58x = 2,320.61 × 935.57
4. Step 4: Simplify right side
   1,681.58x = 2,171,085.52
5. Step 5: Solve for x
   x = 2,171,085.52/1,681.58
6. Step 6: Final answer
   x = 1,291.10