Answer: a(n) = 5 - 3n
the sequence has:
a1 = 2
a2 = -1
a3 = -7
.........
we can see that: a2 - a1 = a3 - a2 = -3
=> the sequence is a arithmetic sequence
=> the distance between the numbers is d = -3
because this sequence is a arithmetic sequence
=> a(n) = a1 + (n - 1)d = 2 + (n - 1).(-3) = 5 - 3n
Step-by-step explanation:
Answer:
50/18 or 2.77
Step-by-step explanation:
So first u have to make the 3 1/3 and 1 1/5 into improper fractions.
Then, you can do the keep, change, flip thing and then u get 10/3 x 5/6 to get 50/18
Lets call x the amount of 18% solution and y the amount of 40% solution, and write as equations the info of the problem:
18x + 40y = 10(20)
x + y = 10
lets multiply the second equation by -18 and add to the first:
18x + 40y = 200
-18x -<span> 18y = -180
</span>----------------------
0 + 22y = 20
y = 20/22 = 10/11
and substitute in the original equation:
x <span>+ y = 10
</span>x = 10 - y
x = 10 - 10/11
x = 110/11 - 10/11
x = 100/11
so they have to use 100/11 liters of 18% solution and 10/11 liters of 40% solution
Answer:
-0.51
Step-by-step explanation: