If C = {integers divisible by 2 from 1 to 25} and D = {integers divisible by 6 from 1 to 30}, what is C ∩ D?

Question

accidentalaichan · Answer

A. { }

B. {2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 30}

C. {6, 12, 18, 24, 30}

D. {6, 12, 18, 24}

zepdrix · Answer

Let's determine what values are inside of C and D.

D contains values divisible by 6.
6 is divisible by 6. $\large 6/6=1$
12 is also divisible by 6. $\large 12/6=2$
18...
24...
30...

So our set D is going to be,
D={6, 12, 18, 24, 30}

Were you able to determine what elements C will contain?

accidentalaichan · Answer

C={2,4,6,8,10,12,14,18,20,22,24} , right?

zepdrix · Answer

Yah that sounds right :)

So we want to figure out what this gives us,

{2, 4, 6, 8, 10, 12, 14, 18, 20, 22, 24} ∩ {6, 12, 18, 24, 30}

The intersection symbol tells us that we only wants elements that appear in `both sets`.

accidentalaichan · Answer

Okay, so 6, 12, 18, 24?

zepdrix · Answer

Yay good job \c:/

= {6, 12, 18, 24}

accidentalaichan · Answer

Thanks :3