10 students averaged 80, so the sum of their scores was (10 x 80) = 800
20 students averaged 89, so the sum of their scores was (20 x 89) = 1,780
All together, the sum of all 30 scores was (800 + 1,780) = 2,580
30 students totaled 2,580, so their average was (2,580 / 30) = <em> 86</em> .
Answer:
I also got 27.44 mg.
Step-by-step explanation:
Use the function given to you:
A(t)=le^rt
l: Initial Amount (50)
r: Rate (-.1) (Negative because the medicine is exiting the bloodstream at 10% per hour
t: 6 (the specific time value you are evaluating the function at.
A(6)=50e^-.1(6)=27.44
9514 1404 393
Answer:
x = 10 2/3
Step-by-step explanation:
The ratios of corresponding sides are the same, so we have ...
x/8 = 8/6
x = 8·(8/6) = 64/6
x = 10 2/3
6*4=24
8*6=48
24/48=4/8=1/2
I hope this helps;)
Y1 is the simplest parabola. Its vertex is at (0,0) and it passes thru (2,4). This is enough info to conclude that y1 = x^2.
y4, the lower red graph, is a bit more of a challenge. We can easily identify its vertex, which is (-4,0), and several points on the grah, such as (2,-3).
Let's try this: assume that the general equation for a parabola is
y-k = a(x-h)^2, where (h,k) is the vertex. Subst. the known values,
-3-(-4) = a(2-0)^2. Then 1 = a(2)^2, or 1 = 4a, or a = 1/4.
The equation of parabola y4 is y+4 = (1/4)x^2
Or you could elim. the fraction and write the eqn as 4y+16=x^2, or
4y = x^2-16, or y = (1/4)x - 4. Take your pick! Hope this helps you find "a" for the other parabolas.
