A student has two summer business. They watch children for $16 an hour and $11 an hour to walk dogs. The students parents only allow them to work at most 30 hours per week. Their goals are to make at least $350 per week Create a system of equations or inequalities that model the situation. Define the variables you use

The probability that fewer than 4 adults use their smartphones in meetings or classes is 0.02019

Using the binomial probability relation :

P(x = x) = nCx * p^x * q^(n-x)

Where :

To define the probability that fewer than 4 use the smartphone in meetings or classes :

P(X < 4) = P(X = 3) + P(x = 2) + P(x = 1) + P(X = 0)

Using a binomial probability calculator :

P(X = 3) = 0.01595

P(x = 2) = 0.00368

P(x = 1) = 0.00052

P(X = 0) = 0.00003

Hence,

P(X < 4) = 0.01595 + 0.00368 + 0.00052 + 0.00003

P(X < 4) = 0.02019

Therefore, the probability of fewer than 4 using their smartphones in meeting or classes is 0.02019.

Learn more :link