Finding the Fourth Proportional to 1,615.31, 2,421.42 and 689.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,615.31 : 2,421.42 = 689.59 : x
2. Step 2: Convert to fraction form
   1,615.31/2,421.42 = 689.59/x
3. Step 3: Cross multiply
   1,615.31x = 2,421.42 × 689.59
4. Step 4: Simplify right side
   1,615.31x = 1,669,787.02
5. Step 5: Solve for x
   x = 1,669,787.02/1,615.31
6. Step 6: Final answer
   x = 1,033.73