Answer:
The answer is 
.
Step-by-step explanation:
First, it is important to recall that the group law is not commutative in general, so we cannot assume it here. In order to solve the exercise we need to remember the axioms of group, specially the existence of the inverse element, i.e., for each element 
there exist another element, denoted by 
such that 
, where 
stands for the identity element of G.
So, given the equality 
we make a left multiplication by 
and we obtain:
But, 
. Hence, 
.
Now, in the equality we make a right multiplication by 
, and we obtain
.
Recall that 
and 
. Therefore,
.
(yX3)+1 because product means multipy
2.) Given: There are 30 students. 24 are wearing sneakers.
Work: We can figure this out by finding the exact percentage of sneaker-wearers in the class.
To find the percentage, you do 24/30. 24/30 is equal to 80%.
Answer: Joe is wrong. The percentage of students wearing sneakers is 80% and not 70%.
3.) Given: There are 40 people total. 2 women per 3 men.
Work: 2:3 women to men
If we multiply both by 10, we will get 50 people in total.
20:30 = 50
So we need to shrivel this down to 40 by taking out 5 on both sides of the ratio.
50 - 5 - 5 = 15:25 = 40
But the ratio need to be divisible by 2 because of the 2 women that are needed per 3 men. We can do this by moving over one human to the men’s side.
There are 14 women and 26 men. I didn’t use any of the strategies there listed because I don’t even remember what those are. I’m in grade 9. I would say that the ratio table works best because I just used ratios...
4.) Given: Find simplified fraction of silicon. 100%.
Work: Add all things up to find out the denominator for the fraction. They will equal 100.
So the fraction is 28/100.
We can divide this fraction by 4.
7/25
This is the simplified form.
Answer: 7/25
