Answer:
C. 41
Step-by-step explanation:
We want to find the number of odd integers from 10 to 51.
The first odd integer from 10 to 51 is 11; the second is 13; the third is 15; and so on until 51. So, our list looks like this:
11, 13, 15, ... , 51
We need to figure out how many numbers there are. Let's add 1 to all of them:
11 + 1, 13 + 1, 15 + 1, ... 51 + 1
12, 14, 16, ... , 52
Now, let's divide by 2:
12/2, 14/2, 16/2, ... 52/2
6, 7, 8, ... , 26
Finally, subtract 5 from them:
6 - 5, 7 - 5, 8 - 5, ... , 26 - 5
1, 2, 3, ... , 21
There are 21 odd integers, so x = 21.
The even integers from 10 to 51 start with 12, 14. They end with 50. So, we have:
12, 14, ... 50
Let's use a similar method as above. Divide by 2:
12/2, 14/2, ... , 50/2
6, 7, ... , 25
Subtract 5:
6 - 5, 7 - 5, ... , 25 - 5
1, 2, 3, ... , 20
There are 20 even integers, so y = 20.
Then, x + y = 21 + 20 = 41.
The answer is thus C.
~ an aesthetics lover
