9514 1404 393
Answer:
34
Step-by-step explanation:
In order to divide some multiple of 15 chocolate bars evenly by 21, the number of bars must be a multiple of the LCM of 15 and 21, which is 105. That number is 7 times 15, indicating the number of boys in the class must be a multiple of 7. The only number between 30-20 = 10 and 40-20 = 20 that is a multiple of 7 is 14.
There must be 14 boys in the class, so 34 students in total.
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The boys brought a total of 210 chocolate bars, so each girl and the teacher received 10 of them.
15=-2(2t-1) -- expand brackets
15=-4t+2 -- subtract 2
13=-4t -- switch signs, best to have a positive variable
4t=-13
t=-13/4
The answer is (x-y)^2
hope it helps!!!!!!
the formula is
(a-b)^2
and when you expand it, it becomes
a^2-2ab+b^2
Area=1/2*base*height
given that ABC is right angled triangle, the height will be given by:
tan theta=opposite/adjacent
tan 60=h/6
h=6tan60
=10.4
thus the area will be:
A=1/2x6x10.4
=31.2 cm^2