Answer:
your sister would be 35
Step-by-step explanation:
<span>1) Find P(E1UE2)
E1 probability= 1/2</span>
<span>There are 26 red cards in a 52 card deck, so the probability of choosing a red card is = 26/52 = 1/2
E2 probability= 12/ 52 or 3/13</span>
<span>The face cards are: Jacks, Queens, and <span>Kings. There are four suits, so in each suit there are one jack, one queen and one king. The probability is 3 x 4= 12 divided by the total number of cards.
2)</span></span><span>the probability of drawing a blue ball on the first draw: 4 /10
</span>the probability of drawing a white ball on the second drawn: 6/9 (because there is less one ball from the previous draw).
the probability of the cases together is 4/15 ( 4 /10 x 6/9) <span>since they are independent cases.</span>
The number who drink coffee is 3/4 of 8000, so ...
... (3/4)×8000 = 6000.
Of those, 1/5 add cream, so the number of coffee drinkers who add cream to their coffee is ...
... (1/5)×6000 = 1200.
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Alternate solutions
We have computed ...
... (1/5)×((3/4)×8000) = 1200
Since multiplication is associative, you can multiply the fractions first, if you wish:
... ((1/5)×(3/4))×8000 = (3/20)×8000
... = 24000/20 = 1200
or
... = 3×(8000/20) = 3×400 = 1200
