Probability of at most 1 brown M&M in 7 draws

[r1terrell23]

Okay so I did this problem and got it wrong but I get one more chance to get it right. I tried using Binomial Dist to solve it but I failed.

30% of all M&Ms are brown. If 7 M&Ms are randomly selected, what is the probability that at most 1 is brown?

I thought I would use 0 and 1 but I guess not. Can someone help me?

 

[mathman]

p₀=.3⁷
p₁=7*.3⁶*.7

Add them up.

 

[mathman]

Sorry, got the probs reversed. switch .3 and .7.

p₀=.7⁷
p₁=7*.7⁶*.3

Add them up.

 

[cactus1003]

For Binomial Distribution,
take n=7, p=0.3, q=1-p=0.7.

P(X<=1)=P(X=0)+P(X=1)=q^7+n*p*q^6

thts it gys...
enjy