Let p be the prize of a pen and m the prize of a mechanical pencils. If you buy six pens and one mechanical pencil, you spend 6p+m. We know that this equals 9, because you get 1$ change from a 10$ bill.
Similarly, if you buy four pens and two mechanical pencils, you spend 4p+2m, which is 8$, because now you get a $2 change. Put these equation together in a system:

Now, if you multiply the first equation by 2, the system becomes

Subtract the second equation from the first:

Plug this value into the first equation to get

Based on the picture, we know that ED is equal to DB. Therefore:
2 times ED=EB
2(10)=20
EB is 20
She could have hiked one 2 mile trail and one 1 mile trail or she could’ve hiked one 2.5 mile trail and another 0.5 mile trail
A) not statistical because there is one correct response, the presidents name.
B) not statistical , because it is a single person answering.
C) Statistical because the number can be change and be used to determine what percent of the population has brown eyes.