Finding the Fourth Proportional to 1,912.67, 2,870.22 and 817.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,912.67 : 2,870.22 = 817.05 : x
2. Step 2: Convert to fraction form
   1,912.67/2,870.22 = 817.05/x
3. Step 3: Cross multiply
   1,912.67x = 2,870.22 × 817.05
4. Step 4: Simplify right side
   1,912.67x = 2,345,113.25
5. Step 5: Solve for x
   x = 2,345,113.25/1,912.67
6. Step 6: Final answer
   x = 1,226.09