Counting problem
\(\large \color{black}{\begin{align} & \normalsize \text{Find the number of natural number solutions of.}\hspace{.33em}\\~\\ & a+2b+c=100 \hspace{.33em}\\~\\ \end{align}}\)
hmm okay
b can be all even numbers
do you know how to solve the simpler version of this problem a+b+c=100
do i need to change 2b to d
sry i mean 2b is all even numbers
99C2
yeah thats right
i meant to use substitution as 2b=d
here is another way u can think about it a+b+b+c = 100 how would you solve this a+b+c+d=100
99C3
i think you would solve a+b+c=100 and divide by 2
as all the odd possibilities would not possible
u mean 99C2/2
yeah but let me think that might not technically be true we dont know if odd and even solutions that add to 100 is exactly equal or not
How about calculatinb a+b1+b2+d=100 and substracting something
?
what do u mean
ok back
okay well maybe we can go back to the stars and bars method after this but i think we can do it with just sums
no wait there are 101 WAYs actually to add upto 100 when u pick 2b=0
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