Answer:
Step-by-step explanation:
The given sequence is
-12,-16,-20...
The first term of this sequence is 
.
The common difference is
The nth term of this arithmetic sequence is;
We substitute the values for the first term and the common difference to obtain;
Answer:
the answer is C
Step-by-step explanation:
Answer:
si
Step-by-step explanation:
Let <em>q</em> be the number of quarts of pure antifreeze that needs to be added to get the desired solution.
8 quarts of 40% solution contains 0.40 × 8 = 3.2 quarts of antifreeze.
The new solution would have a total volume of 8 + <em>q</em> quarts, and it would contain a total amount of 3.2 + <em>q</em> quarts of antifreeze. You want to end up with a concentration of 60% antifreeze, which means
(3.2 + <em>q</em>) / (8 + <em>q</em>) = 0.60
Solve for <em>q</em> :
3.2 + <em>q</em> = 0.60 (8 + <em>q</em>)
3.2 + <em>q</em> = 4.8 + 0.6<em>q</em>
0.4<em>q</em> = 1.6
<em>q</em> = 4
Answer:
8 hours
Step-by-step explanation:
12/2= 6
He grades 6 exams per hour
48/6= 8
it would take 8 hours to grade 48 exams
Bonus:
it takes him 10 minutes to grade an exam. That doesnt matter for this question but it's good 2 know
