Answer:
79687
Step-by-step explanation:
Answer:
15.

16. 10 ml of 20% saline and 40 ml of 10% saline
Step-by-step explanation:
A chemist takes x ml of 20% saline and y ml of 10% saline. In total, he takes
x + y ml that is 50 ml, so

There are
ml of salt in x ml of 20% saline and
ml of salt in 10% saline. There are
ml of salt in 50 ml of 12% saline. Thus,

15. We get the system of two equations:

16. Solve this system. From the first equation:

Substitute it into the second equation:

Answer:
25 I think.
Step-by-step explanation:
I just did 5x5 soo....
Answer:
The first term of the sequence is -120.
Step-by-step explanation:
The formula for the "nth" term of a geometric sequence is shown below:
an = a0*r^(n-1)
Where an is the nth term, r is the ratio and n is the position of the term on the sequence. For this problem we want to find what is the initial term, a0, so we will isolate it in the formula as shown below:
a0*r^(n-1) = an
a0 = an/[r^(n-1)]
We then apply the data given to us
a0 = 31.45728/[-0.8^(7-1)]
a0 = 31.45728/[-0.8^6] =31.45728 /-0.262144= -120
The first term of the sequence is -120.