Finding the Fourth Proportional to 1,445.03, 1,993.98 and 815.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,445.03 : 1,993.98 = 815.55 : x
2. Step 2: Convert to fraction form
   1,445.03/1,993.98 = 815.55/x
3. Step 3: Cross multiply
   1,445.03x = 1,993.98 × 815.55
4. Step 4: Simplify right side
   1,445.03x = 1,626,190.39
5. Step 5: Solve for x
   x = 1,626,190.39/1,445.03
6. Step 6: Final answer
   x = 1,125.37