Finding the Fourth Proportional to 1,680.30, 2,517.56 and 1,310.84

Step by Step Solution

1. Step 1: Write the proportion equation
   1,680.30 : 2,517.56 = 1,310.84 : x
2. Step 2: Convert to fraction form
   1,680.30/2,517.56 = 1,310.84/x
3. Step 3: Cross multiply
   1,680.30x = 2,517.56 × 1,310.84
4. Step 4: Simplify right side
   1,680.30x = 3,300,099.21
5. Step 5: Solve for x
   x = 3,300,099.21/1,680.30
6. Step 6: Final answer
   x = 1,963.99