Finding the Fourth Proportional to 1,561.39, 2,154.69 and 862.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,561.39 : 2,154.69 = 862.75 : x
2. Step 2: Convert to fraction form
   1,561.39/2,154.69 = 862.75/x
3. Step 3: Cross multiply
   1,561.39x = 2,154.69 × 862.75
4. Step 4: Simplify right side
   1,561.39x = 1,858,958.80
5. Step 5: Solve for x
   x = 1,858,958.80/1,561.39
6. Step 6: Final answer
   x = 1,190.58