Finding the Fourth Proportional to 2,175.69, 3,002.91 and 1,389.60

Step by Step Solution

1. Step 1: Write the proportion equation
   2,175.69 : 3,002.91 = 1,389.60 : x
2. Step 2: Convert to fraction form
   2,175.69/3,002.91 = 1,389.60/x
3. Step 3: Cross multiply
   2,175.69x = 3,002.91 × 1,389.60
4. Step 4: Simplify right side
   2,175.69x = 4,172,843.74
5. Step 5: Solve for x
   x = 4,172,843.74/2,175.69
6. Step 6: Final answer
   x = 1,917.94