hopefully this answer can help you to answer the next question
Its just a matter of subbing ur numbers into the formula given
1. d = rt
when r = 144 and t = 18
now we sub
d = 144 * 18
d = 2592 <==
2. d = rt
when r = 56 and t = 3.5
sub
d = 56 * 3.5
d = 196 <==
3. A = L * W
when L = 2 ft and W = 15 inches....this one u have to convert to inches...2 ft = 24 inches...so L = 24 and W = 15
A = 24 * 15
A = 360 in^2 <==
4. A = L * W
L = 3m and W = 32 cm...have to convert to cm.....1 m = 100 cm...so 3 m = 300 cm
A = 300 * 32
A = 9600 cm^2 <==
u basically do the same for all the others....its just a matter of subbing and solving
Answer:
5.78% probability that exactly 2 of them use their smartphones in meetings or classes.
Step-by-step explanation:
For each adult, there are only two possible outcomes. Either they use their smarthphone in meetings or classes, or they do not. The probability of an adult using their smartphone on meetings or classes is independent of other adults. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
63% use them in meetings or classes.
This means that 
7 adult smartphone users are randomly selected
This means that 
Find the probability that exactly 2 of them use their smartphones in meetings or classes.
This is P(X = 2).


5.78% probability that exactly 2 of them use their smartphones in meetings or classes.
Answer:
1992
Step-by-step explanation:
60x38=2280
32x9=288
2280-288=1992
Hope it helps!