Luke was born on October 1, 2009. His grandparents put $20,000 into an account that

30,200$

Step-by-step explanation:

3 times 17 is 51 which is interesting and 1.51 times 20,000 is 30,200$.

I suppose you're supposed to prove that set intersection is distributive across a union,

Two sets are equal if they are subsets of one another. To prove a set is a subset of another set , you have to show that any element also belongs to .

Let . By definition of intersection, both and . By definition of union, either or . If , then clearly ; if , then . Either way, . Hence .

The proof in the other direction uses the same sort of reasoning. Let . Then either or . If , then both and ; if , then both and . So certainly , and either or so that . Hence .

Both sets are subsets of one another, so they are equal.