Clara will she will have 16 phone calls while Toby will have 15
The inclusion/exclusion principle states that

That is, the union has as many members as the sum of the number of members of the individual sets, minus the number of elements contained in both sets (to avoid double-counting).
Therefore,

will have the most elements when the sets

and

are disjoint, i.e.

, which would mean the most we can can in this case would be

(Note that

denotes the cardinality of the set

.)
Answer: Your brother is 15 years old right now.
Step-by-step explanation:
Let be "m" your currently age and "b" your brother's currently age.
Knowing that right now he is three times (this indicates multiplication) as old as you, you can write the following equation:

In five years your age will be:

And your brother's age will be:

Then, if in five years, your brother will be twice as old as you, you can set up the second equation:

Then, the System of equations is:

Apply the Substitution method and substitute the first equation into the second one and solve for "m":

Substitute the value of "m" into the first equation and evaluate in order to find "b":

Answer:
its Pp or it could also be nonexistent
Answer:
where's the graph ??
Step-by-step explanation: