Maths help

[OverProtectiveMumOfPFB]

Before I embarrass myself asking DH please!

Can't figure out how to do greater than or equal to sign so using <= and >=

which numbers could Z be?
A) Z + 3 < 10
Z + 3 <= 10

B) Z + 3 > 10
Z +3 >= 10

C) 3 x Z < 21
3 x Z <= 21

D) 3 x Z > 21
3 x Z >= 21

E) which number can Z in the expressions A to D not be?

Have no idea what the answer to E is supposed to be.
other answers are
A) 0-6; 0-7
B) any number greater than 8; any number greater than 7
C) 0-6; 0-7
D) any number greater than 8; any number greater than 7

Z plus 3 is less than 10, so Z must be less than 7 (not including 7)

Z plus 3 is less than or equal to 10 means Z is less than or equal to 7.

www.bbc.co.uk/bitesize/guides/z9ck7ty/revision/1

Does that help?

What is it that you don't get about the symbols?

I don't get how to type them!

and I don't know the answer to E.

Answers to A-D are known.

Do it in words. Z plus 3 is less than ten so Z must be less than 7. And when Z plus 3 is less than or equal to ten, Z must be less than or equal to 7. Does that make it make more sense?
If you work through on my logic, the answer is 7 to all of them with whichever sign it is in the question. (Think about fractions as well)
So when you get to E, the only number it can't be in A-D (which I assmume means the top line of each with <> not <=>=) is 7 because it has to be either bigger or smaller depending on the question. Sorry posting on app so I'm finding it hard to remember what the questions are.
When you're solving inequalities, you can stick your finger over the inequality sign and imagine it's =, and solve it as an equation, and just write the inequality back in at the end.

So Z can't be 7 in any of the answers for the first parts of the expressions where there is no equals signs because the answers are either greater than or less than 7 and don't include 7. Does that make sense? I'll write it on paper if you need because I don't know how to type them either!)

In A) is there a reason that you're giving answers 0-6 by the way? Z could be any value, including decimals and negatives as long as it is less than 7.

So Z = 6.9999 for example or Z = -155!

Yeah, says whole numbers only.

yes, can't be 7 for the first one of each, but it doesn't ask that.

Can you attach a picture of the exercise? I'm curious how it's set out now!

We've gone for:

In the top line of A-D the answer can't be 7.