Finding the Fourth Proportional to 1,508.10, 2,081.28 and 918.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,508.10 : 2,081.28 = 918.69 : x
2. Step 2: Convert to fraction form
   1,508.10/2,081.28 = 918.69/x
3. Step 3: Cross multiply
   1,508.10x = 2,081.28 × 918.69
4. Step 4: Simplify right side
   1,508.10x = 1,912,051.12
5. Step 5: Solve for x
   x = 1,912,051.12/1,508.10
6. Step 6: Final answer
   x = 1,267.85