For this problem you have yo set up two equations.
White shirts = w Yellow shirts = y
1st: w + y = 21
2nd: 9.95w + 11.50y = 235.30
Now we're going to do system of equations using substitution.
If w + y = 21, then y = 21 - w
If y = 21 - w, then you can substitute this in the second equation for y.
9.95w + 11.50(21 - w) = 235.30
9.95w + 241.5 - 11.50w = 235.30
-1.55w + 241.5 = 235.30
-1.55w = -6.2
w = 4, so 4 whites shirt were sold.
Now I'm finding out how many yellow shirts were sold using one of the two equations at the top.
w + y = 21
4 + y = 21
y = 17
So 17 yellow shirts were sold and 4 white shirts were sold.
Answer:
Mai lives 384 miles away from the mountains
Step-by-step explanation:
Let d represent distance between Mai's house and mountains and r represent Mai's rate while going to mountains.
We have been given that there was heavy traffic on the way there, and the trip to mountains took 8 hours.
We are also told that when Mai drove home, there was no traffic and the trip only took 6 hours. Her average rate was 16 miles per hour faster on the trip home.
Upon equating equation (1) and equation (2), we will get:
Upon substituting in equation (1), we will get:
Therefore, Mai lives 384 miles away from the mountains.
Answer:
V(max) = 8712.07 in³
Dimensions:
x (side of the square base) = 16.33 in
girth = 65.32 in
height = 32.67 in
Step-by-step explanation:
Let
x = side of the square base
h = the height of the postal
Then according to problem statement we have:
girth = 4*x (perimeter of the base)
and
4* x + h = 98 (at the most) so h = 98 - 4x (1)
Then
V = x²*h
V = x²* ( 98 - 4x)
V(x) = 98*x² - 4x³
Taking dervatives (both menbers of the equation we have:
V´(x) = 196 x - 12 x² ⇒ V´(x) = 0
196x - 12x² = 0 first root of the equation x = 0
Then 196 -12x = 0 12x = 196 x = 196/12
x = 16,33 in ⇒ girth = 4 * (16.33) ⇒ girth = 65.32 in
and from equation (1)
y = 98 - 4x ⇒ y = 98 -4 (16,33)
y = 32.67 in
and maximun volume of a carton V is
V(max) = (16,33)²* 32,67
V(max) = 8712.07 in³
