Your question, your audience. Choose who sees your identity—and your question—with question security.

Hi guys: Can any one please help me in that question ? Thanks.

How many integers in the set {n belongs to Z | 1 less than equals to n less than equals to 700} are divisible to 2 or 7 ?

How many integers in the set {n belongs to Z | 1 less than equals to n less than equals to 700} are divisible to 2 or 7 ?

How many are divisible by 2 (easy)

How many are divisible by 7 (also easy)

How many are divisible by both (not too hard)

Once you have those, the answer should be pretty easy to come up with (please no one jump in with just the answer).

well half of the divisible by 7 will also be divisible by 2....

(7,14,21,28,35,42,etc easy to see that half are pair)

so 50 will be divisible by both

All Courses

From novice to tech pro — start learning today.

that doesn't make sense...

you probably meant

1 <= n <= 700

So the set is integers from 1 to 700 ?

then it shouldn't be too hard...

one in seven will be divisible by 7... so 100

one in 2 is divisible by 2... so 350