Answer:
0.4
Step-by-step explanation:
so, Katherine can do 0.1 of the job per hour. (if she needs 10 hours for the job, each hour she can do the whole divided by the time, so 1/10, which is 0.1)
if in two hours she and Marina can be done, then Marina will do 1(the whole job)-2/10 (twice as much as she can do in an hour)=0.8 of the job. So if Marina does 0.8 of the job in two hours, each hour she will do half of it: 0.4 - and this is the correct answer
Hello there!
I'm assuming since there is no question, that you want an explanation for composite functions.
Today, I want to introduce you to a very new way of looking at functions. Think of a function as a machine. I'll call this machine f. When you plug something into this machine, it is an x-value. The machine changes the x-value into a new value which is called a y-value. This is how a function works.
With composite functions though, things get a little bit tricky. To make f(g(x)), you need to plug in x into the g machine, and it will give you an output. (y-value) The next thing you do is take that y-value and plug it into the g machine. The g machine then gives you a new value. This value is f(g(x)).
Let's do an example together...
f(x)=3x and g(x)=x²+4
if we want f(g(x)), first plug in x to the g machine. when plugging in x to the g machine, we get x²+4 as given in the question.
Now we must plug in g(x) into the f machine. Since g(x) is x²+4, we just replace x with x²+4.
We get 3(x²+4)
This means that f(g(x))=3(x²+4)
NOTE: If you are seeking help with an actual question, please message me in the comments and I will assist you shortly!
I hope this helps!
Best wishes :)
Answer: 3
Step-by-step explanation:
The answer is 4 isn’t it?