Answer:
<em>She needs </em><em>77 </em><em>on her last test to earn an 82 for the quarter.</em>
Step-by-step explanation:
Maria scored 72, 97, and 82 on her first three math tests.
She wants to have a mean score of 82 for the quarter.
Let us assume that she must score x on her last test to earn an 82 for the quarter.
So the average score will be,
But the average score is given as 82, so
Answer:
The ideal size will be a 45cmx45cm square, giving you a perimeter of 180cm.
Step-by-step explanation:
The shortcut answer here is that the square will always be the most efficient rectangle for border to area, so the sides should be the square root of 2025 cm, or 45 cm each, giving you a total of 180 minimum perimeter.
The full solution is to express the perimeter as a function of the length and width, define either length or width as a function of the other, take the entire expression's derivative and solve for zero. Let's do it:
So first the area:
2025 = wl
l = 2025 / w
Now the sides:
Then we can take its derivative with respect to w
Now we can set the derivative to zero, and solve for w:
So the width being 45, we can get the length by dividing the area by that amount, which of course is also 45.
Answer:
-48 ; - 16
Step-by-step explanation:
Given the expression :
X /4 = - 12
Multiply both sides by 4
X/4 * 4 = - 12 * 4
X = - 48
For the second :
X/2 = - 8
Multiply both sides by 2
X/2 * 2 = - 8 * 2
X = - 16
Answer is D. 3000. This is because 1.2*10^3=1200 and 4*10^-1=.04 so using the equation .4x=1200 when x=300 makes the equation true.
Answer:
z=-5
Step-by-step explanation:
divide -77.5 by 15.5, which equals -5