400
Explanation:
1/3 of 600 is 200. That represents the boys.
Subtract 200 from 600, you get 400. That represents everybody else in the sample size (in this case, girls).
First question : A
2cm×1cm×2+2cm×4cm×2+1cm×4cm×2= 28cm^2
Third question
7x+3(x-2)-4x+8
= 7x+3x-6-4x+8
=7x+3x-4x-6+8
=10x-4x+2
=6x+2
Idon't know the second one but i hope i could still help
You subtract the 12 and 3 and then add the 3+5 and you get 9x+8
She took 100, the store has - 100
she went back and bough
70 bucks in stuff, the store has - 70
yes, she took the $100 bill and gave it, got back $30, that means she only kept $30 from the original bill.
the store however, lost the original $100 bill plus the $70 in merchandise, so they have -$170.