You'd need to start by finding what 40% of 280 is. To do this, you turn 40% into a decimal which is .40 . Multiply .40 x 280 which is 112. Then subtract that answer from 280 which is 168 baseball cards. Hope this helped :)
This is how it would look on a graph.
Step-by-step explanation:
p = 0.1, q = 0.9, n = 7
a) Use complementary probability.
P(at least 1) = 1 − P(0)
P(at least 1) = 1 − (0.9)⁷
P(at least 1) = 0.522
b) Use binomial probability.
P = nCr pʳ qⁿ⁻ʳ
P(3) = ₇C₃ (0.1)³ (0.9)⁴
P(3) = 0.023
I think I just had a stroke trying to read this
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