How do I Express the inequality x < 7 using interval notation.

You can write this as (-infinity, 7) if you aren't able to use the infinity symbol.

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Explanation:

Think of x < 7 as writing

So x is between negative infinity and 7, excluding both endpoints.

To write in interval notation, we write

The curved parenthesis tell us to exclude the endpoint.

b) 1/3 * 1/5

step-by-step explanation:

each smallest part is 1/15 since the written one is 1/5 and it's divided by 3 equal parts. (1/5 )/3 = 1/15 = 1/3 * 1/5