Answer:
a₂₁ = 638
Step-by-step explanation:
substitute n = 21 into the explicit formula
a₂₁ = - 2 + 32(21 - 1) = - 2 + 32(20) = - 2 + 640 = 638
Answer:
(D) 
Step-by-step explanation:
Two variables x and y are proportionally related if they can be written in the form y=kx, where k is the constant of proportionality.
From the given options, if 
(B)
is of the form y=kx
(C)
is of the form y=kx with
as
in its lowest form.
(C)
is of the form y=kx with
as
in fractional form.
On the Contrary,
In Option D,
does not represent a proportional relationship between x and y. The constant of proportion is supposed to be a product of x.
The ratio is:
Chlorine : Water = 1 : 10
m ( Water ) = 15 ounces
m ( Chlorine ) = x
x : 15 = 1 : 10
10 x = 15 * 1
10 x = 15
x = 15 : 10
x = 1.5 ounces
Answer:
We need to add 1.5 ounces of Chlorine for the correct ratio.
You should definitely improve the quality of the image, because I can't see anything clearly.
Also, the 4th answer is hidden.
Answer:
1/45
Step-by-step explanation:
There are 10 marbles
P ( yellow) = yellow marbles / total = 2/10 = 1/5
We do not replace the marble
There are 9 marbles, 1 of which is yellow
P ( yellow) = yellow marbles / total = 1/9
P ( yellow, no replacement, yellow) = 1/5 * 1/9 = 1/45