Let "some number" be denoted by the variable, x. Change the word expression into expression:
The sum of some number (x) and 82:
Sum means adding, and so you will add x with 82.
x + 82
The quotient of x minus 6 and 8:
Note the term "x minus 6", which means that it would be the first order of operations to be solved. Therefore, you must give it parenthesis. Tack on the quotient 8 and you will have your answer:
(x - 6)/8
Some number divided by 4:
Let "some number" be denoted by the term x. Divide it by 4:
x/4
"The product of y and twice as much as y":
Note that product means multiply.
y * 2y
Then add 3:
2 * 2y + 3
As for the second part:
25x - 5 should be the 2nd choice.
5x - 25 is correct in being the 1st choice.
I am not sure about the wording of the second option, but given that it is the last choice then obviously the 3rd one will be the choice.