Answer all the questions below and press submit to see how many you got right.
Count : To count means to find out the number of objects by adding one for every object.
Divisible by 2 : An integer $x$ is called divisible by 2 if $x$ is a multiple of 2. An integer is divisible by 2 if and only if it is even.
Divisible by 3 : An integer $x$ is called divisible by 3 if $x$ is a multiple of 3. An integer is divisible by 3 if and only if the sum of its digits is divisible by 3.
Divisible by 6 : An integer $x$ is called divisible by 6 if $x$ is a multiple of 6. An integer is divisible by 6 if and only if it is even and the sum of its digits is divisible by 3.
Number : A number $x$ is a mathematical symbol representing a quantity.
Set : A set is a collection of objects.
Sum : A sum is the result of an addition.
In a set of 40 numbers 15 numbers are divisible by 2, 14 are divisible by 3 and 19 are neither divisible by 2 or by 3. How many numbers in the set are divisible by 6?
In a restaurant the guests can choose a main out of 8 pizzas and 4 pastas. How many main courses are there?
Divisible by 4 : An integer $x$ is called divisible by 4 if $x$ is a multiple of 4. An integer is divisible by 4 if and only if the last two digits form a number that is divisible by 4.
How many of the numbers in 1,2,3,...,921 are not divisible by 4?