Finding the Fourth Proportional to 1,570.05, 2,166.69 and 861.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,570.05 : 2,166.69 = 861.96 : x
2. Step 2: Convert to fraction form
   1,570.05/2,166.69 = 861.96/x
3. Step 3: Cross multiply
   1,570.05x = 2,166.69 × 861.96
4. Step 4: Simplify right side
   1,570.05x = 1,867,593.06
5. Step 5: Solve for x
   x = 1,867,593.06/1,570.05
6. Step 6: Final answer
   x = 1,189.51