Yea you right but you get it on °F but i need on °C so i put it into °C=5/9(°F-32) and get (A)
Why (E) ?
Tenth is need to one digit after the 0 so the answer need to be 0 :)
I found the answer (A)
https://www.google.az/search?q=trapezoid&espv=2&biw=1366&bih=667&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjNhPLYpIzKAhUEFCwKHSLUDhQQsAQIJQ#tbm=isch&q=trapezoid+volume&imgrc=UjjItkeRiDNULM%3A
Omi 67 :DD
because 100-15= i get 75 D
10.20x4=40.8 it is the price of gift whith discount
x-0.15x=40.8
75x/100=40.8
x=40.8x100/75
x=54.4 is original price
i am not sure :)
http://www.wolframalpha.com/input/?i=%283x%5E2-21x%2F6x%2B8%29%2F%28x%5E3-14x%5E2%2B49x%2F15x%2B20%29
Thanks CPhill ! :)
