Finding the Fourth Proportional to 1,499.65, 2,249.61 and 678.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,499.65 : 2,249.61 = 678.31 : x
2. Step 2: Convert to fraction form
   1,499.65/2,249.61 = 678.31/x
3. Step 3: Cross multiply
   1,499.65x = 2,249.61 × 678.31
4. Step 4: Simplify right side
   1,499.65x = 1,525,932.96
5. Step 5: Solve for x
   x = 1,525,932.96/1,499.65
6. Step 6: Final answer
   x = 1,017.53