Question

Help me pls and thank you :)

Answer 1

First you have to add :-

X = 7+2+5+9+6+10+9+8+4

X= 50

Y = 2+5+7+4+2+9+9+4+10

Y = 52

Now ,

Σ(xy)= 50×52

= 2600

Hope it helpful to you

Answer 2

Answer: 350

Step-by-step explanation:

Spreadsheet software is strongly recommended. If you have excel, then it's best to use it since it's used practically everywhere. If you don't have excel, then there are tons of free alternatives such as OpenOffice or LibreOffice.

Enter the data as shown. Then form a third column labeled xy which represents multiplying each x and y pair for any given row. Eg: Tom = xy = 7*2 = 14. Use cell references to quickly compute this new column. I don't recommend manually multiplying each pair of items.

Once the xy column is formed, add up everything in it since
`\Sigma` represents summations. The command called "Sum" or "SUM" does this very quickly. In a cell off to the side type in
`=Sum(C2:C10)` which will add up the elements in cell C2, C3, ... all the way up to C10. Don't forget about the equal sign up front. That's needed to execute the command rather than print out text.

The result of the command should be 350

To verify you can manually add up the values to check the answer is correct.