E, because he is stealing everything, meaning he has a net profit. So, you would add everything. Since he 280 $1 bills, he just stole $280 which is a definite quantity, so we don't need a variable for it. Since everything else are indefinite quantities, we need variables (x, y, z). But, yeah, E should be the answer.
8-2=6
10+6+3=19
I’m not sure if you are allowed to do it that way so I can find other ways if needed
7 % of cost price is 2.80 , What about 1%?
7 = 2.80
1 = x (where x is the price value of 1% in dollars)
We simplify the above equation, so:
7 × x = 2.8 × 1 → 7x = 2.8 → x = 2.8 / 7 → x = 0.4 dollars
We know that 100% represents the whole price,
so if 1% is 0.4 dollars, then 100% will be 0.4 × 100 = 40 dollars
Therefore the store charged $40 dollars for the helmet before tax
