Finding the Fourth Proportional to 1,559.63, 2,150.35 and 999.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,559.63 : 2,150.35 = 999.18 : x
2. Step 2: Convert to fraction form
   1,559.63/2,150.35 = 999.18/x
3. Step 3: Cross multiply
   1,559.63x = 2,150.35 × 999.18
4. Step 4: Simplify right side
   1,559.63x = 2,148,584.22
5. Step 5: Solve for x
   x = 2,148,584.22/1,559.63
6. Step 6: Final answer
   x = 1,377.62