Finding the Fourth Proportional to 1,509.69, 2,083.73 and 920.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,509.69 : 2,083.73 = 920.72 : x
2. Step 2: Convert to fraction form
   1,509.69/2,083.73 = 920.72/x
3. Step 3: Cross multiply
   1,509.69x = 2,083.73 × 920.72
4. Step 4: Simplify right side
   1,509.69x = 1,918,516.86
5. Step 5: Solve for x
   x = 1,918,516.86/1,509.69
6. Step 6: Final answer
   x = 1,270.80