Since each trial has the same probability of success,
Let, <span><span><span>Xi</span>=1</span></span> if the <span><span>i<span>th</span></span></span> trial is a success (<span>0</span> otherwise). Then, <span><span>X=<span>∑3<span>i=1</span></span><span>Xi</span></span><span>X=<span>∑<span>i=1</span>3</span><span>Xi</span></span></span>,
and <span><span>E[X]=E[<span>∑3<span>i=1</span></span><span>Xi</span>]=<span>∑3<span>i=1</span></span>E[<span>Xi</span>]=<span>∑3<span>i=1</span></span>p=3p=1.8</span><span>E[X]=E[<span>∑<span>i=1</span>3</span><span>Xi</span>]=<span>∑<span>i=1</span>3</span>E[<span>Xi</span>]=<span>∑<span>i=1</span>3</span>p=3p=1.8</span></span>
So, <span><span>p=0.6</span><span>p=0.6</span></span>, and <span><span>P{X=3}=<span>0.63</span></span><span>P{X=3}=<span>0.63</span></span></span>
I thought what I did was sound, but the textbook says the answer to (a) is <span>0.60.6</span> and (b) is <span>00</span>.
Their reasoning (for (a)) is as follows:
Answer:
Step-by-step explanation:
4) 35x + 28y =7*5*x + 7*4*y = 7(5x + 4y)
5) Cost of top = $9
Cost of 3 top = 9*3 = $27
Cost of skirt = $x
Cost of 3 skirt = 3x
Cost of 3 skirt and 3 top = 3x + 27
Cost of 2 skirt = 2x (as she bought 5 skirts)
Cost of her purchase = Cost of 3skirt &3 top and 2skirt
= (3x + 27) + 2x
= 5x +27
6) Cost of 5 nail polish bottle = 5p
Cost of two lip gloss tube = 2g
Cost of one gift bag = 5p + 2g
Cost of 8 gift bag = 8* ( 5p + 2g)
=8*5p + 8*2g
= 40p + 16g
Answer:
Y = 1/3x + 2
Step-by-step explanation:
Since the line increases by 1 unit then goes to right 3 units the line equation must have a slope of 1/3 and must have a y intercept of + 2 since the line crosses the Y axis at +2
Answer: -1>n
Step-by-step explanation:1) combine like terms (-5n+2n=-3n) so you have 3<-3n then you divide -3 on both sides and because it’s a negative you flip the sign so you end up with -1>n
Answer:
Step-by-step explanation:
The exponent "product rule" tells us that, when multiplying two powers that have the same base, you can add the exponents. In this example, you can see how it works. Adding the exponents is just a short cut! The "power rule" tells us that to raise a power to a power, just multiply the exponents.
