Finding the Fourth Proportional to 1,653.72, 2,480.52 and 678.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,653.72 : 2,480.52 = 678.72 : x
2. Step 2: Convert to fraction form
   1,653.72/2,480.52 = 678.72/x
3. Step 3: Cross multiply
   1,653.72x = 2,480.52 × 678.72
4. Step 4: Simplify right side
   1,653.72x = 1,683,578.53
5. Step 5: Solve for x
   x = 1,683,578.53/1,653.72
6. Step 6: Final answer
   x = 1,018.06