Finding the Fourth Proportional to 1,508.72, 2,082.15 and 870.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,508.72 : 2,082.15 = 870.87 : x
2. Step 2: Convert to fraction form
   1,508.72/2,082.15 = 870.87/x
3. Step 3: Cross multiply
   1,508.72x = 2,082.15 × 870.87
4. Step 4: Simplify right side
   1,508.72x = 1,813,281.97
5. Step 5: Solve for x
   x = 1,813,281.97/1,508.72
6. Step 6: Final answer
   x = 1,201.87