Answer: 0.951%
Explanation:Note that in the problem, the scenario is either the adult is using or not using smartphones. So, we have a yes or no scenario involved with the random variable, which is the number of adults using smartphones. Thus, the number of adults using smartphones follows the binomial distribution.
Let x be the number of adults using smartphones and n be the number of randomly selected adults. In Binomial distribution, the probability that there are k adults using smartphones is given by

Where p = probability that an adult is using smartphones = 54% (since 54% of adults are using smartphones).
Since n = 12 and k = 3, the probability that fewer than 3 are using smartphones is given by

Therefore, the probability that there are fewer than 3 adults are using smartphone is 0.00951 or
0.951%.
Answer:
x = -3/2y + 3
Step-by-step explanation:
2x + 3y = 6
2x = -3y + 6
x = -3/2y + 3
1) 2 with a small 4 at the top like an exponent
Let x be the number of children
Let y be the number of adults
x + y = 4
4x + 7y = 19