Among smartphone users, 40% use a case but no screen protector, 10% use a screen protector but no case, 45% use both a case and a screen protector, and 5% use neither a case nor a screen protector. Twenty smartphone users are sampled at random. Let X1, X2, X3, X4 be the respective numbers of users in the four given categories.

Find P(X1=7, X2=3, X3=8, X4=2).

answer:   expression= p+p*d%

price reduction + sale price = $625

sale price: $p+$p*d%

where d% is the percentage of discount

step-by-step explanation:

original price = p

price went down by $150 price reduction $p*d%

sale price= $ 475

therefore the price before sale is: $625

and the expression that shows the price before sale is: p+p*d%

answer: it is 8

step-by-step explanation:

you know why its 8

an = 22 + (n-1) *6

110 seats

step-by-step explanation:

an=a1+(n-1)(d)

a1 = 22   this is the first item in the sequence

d =6   this is how the sequence goes up

a)   an = 22 + (n-1) *6

b) a12 = 22 + (12-1) *6

    a12 = 22+11*6

  a12 = 22 +88

  a12 = 110

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dfj dt

step-by-step explanation:

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