Answer:

Step-by-step explanation:
Hi,
We know that
P(A or B)=P(A)+P(B)-P(A and B)
so P(B)= P(A or B) - P(A) + P(A and B)
so
P(B) = 0.5 - 0.4 + 0.2 = 0.3
thanks
4 x 22 =?
the question mark is how old they'll be.
Answer:
4) 6 students
5) 7 fewer students
6) No, you can not tell from the frequency table how many students ran a mile in exactly 12 minutes.
Step-by-step explanation:
4) you’d look at the row from 8:00-8:59.
5) Add the first two rows together (6+2=8), then subtract that by the sum of the last two rows (9+6=15), which is 7
6) There’s no pattern in the frequency table, and the data points would be plotted differently since it’d be from a range of times, not one set time.
Hope this helped, sorry if I’m wrong on #6 ;)
Answer: 0.238853503185
(I obviously used a calculator.)
If you rounded this answer, it would be 0.24. Hope this helps!
Answer:
The required probability is, 0.78
Step-by-step explanation:
There are, (52 - 13) = 39 cards which are not spade
5 cards can be chosen from the deck of 52 cards in
ways
and out of these 5 choices, none of them will be spade in,
ways
So,
P(None of the chosen cards is spade)
= 

Hence,
P(out of these 5 choices, at least one card is spade)

= 0.78