Step-by-step explanation:
sum of the arithmetic sequence
a1 = 8
a2 = a1 + 8 = 8+8 = 16
...
an = 8×n
the sum of the first n elements of such a series is
n/2 × (2×a1 + (n - 1)×d]
with d being the difference between 2 consecutive elements (= the added constant).
so,
s30 = 30/2 × (2×8 + 29×8) = 15×(31×8) = 3720
If he failed it once, then the probability out of two times is 1/2. He has a 50% chance of failing the drug test again.
I hope this helps!
The first thing we must do for this case is to define variables:
x: the total mass of the chemical in the container
y: a sample of a chemical from a container
We have the following equation:
y = (3/10) x - 5 3/4
Then, for y = 39.1 we have:
39.1 = (3/10) x - 5 3/4
Clearing x:
(3/10) x = 39.1 + 5 3/4
(3/10) x = 44.85
x = (10/3) * (44.85)
x = 149.5 grams
Answer:
the total mass in grams of the chemical in the container before the scientist removed the sample of 39.1 grams was:
x = 149.5 grams.
The answer is 98-40 square root 6
The answer would be “D” because it’s is 4 less than 7j.