Finding the Fourth Proportional to 1,419.69, 2,128.78 and 494.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,419.69 : 2,128.78 = 494.98 : x
2. Step 2: Convert to fraction form
   1,419.69/2,128.78 = 494.98/x
3. Step 3: Cross multiply
   1,419.69x = 2,128.78 × 494.98
4. Step 4: Simplify right side
   1,419.69x = 1,053,698.82
5. Step 5: Solve for x
   x = 1,053,698.82/1,419.69
6. Step 6: Final answer
   x = 742.20