Answer:
5 marbles are black.
Step-by-step explanation:
7-2=5
Answer:
im pretty sure it is 113.
Step-by-step explanation:
To find a percentage of a number we multiply the percentage times the number and get the result, here we have the percentage and the result and need to find out which number it corresponds to, lets write an equation to do so and keep in mind that the percentage itself can be written in a different way:
225% = 225 out of 100 = 225/100
So we have this equation, where we call x the number we are looking for:
<span>(225%)(x) = 81
</span>(225/100)(x) = 81
so we solve for x:
225x = 81*100 = 8100
x = 8100/225
x = 36
The original number is 36, hence 225% of 36 is 81
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,
.
