Finding the Fourth Proportional to 1,038.42, 1,413.72 and 1,021.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,038.42 : 1,413.72 = 1,021.14 : x
2. Step 2: Convert to fraction form
   1,038.42/1,413.72 = 1,021.14/x
3. Step 3: Cross multiply
   1,038.42x = 1,413.72 × 1,021.14
4. Step 4: Simplify right side
   1,038.42x = 1,443,606.04
5. Step 5: Solve for x
   x = 1,443,606.04/1,038.42
6. Step 6: Final answer
   x = 1,390.19