Finding the Fourth Proportional to 1,413.20, 1,948.16 and 1,019.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,413.20 : 1,948.16 = 1,019.60 : x
2. Step 2: Convert to fraction form
   1,413.20/1,948.16 = 1,019.60/x
3. Step 3: Cross multiply
   1,413.20x = 1,948.16 × 1,019.60
4. Step 4: Simplify right side
   1,413.20x = 1,986,343.94
5. Step 5: Solve for x
   x = 1,986,343.94/1,413.20
6. Step 6: Final answer
   x = 1,405.56