The first on is this answer here
Answer:
The concentration is simply 36%
Step-by-step explanation:
In this question, we are concerned with calculating the concentration of a new mixture formed from mixing some liters of each of two vinegar variants of different concentrations.
We proceed as follows;
The concentration of the new solution will contain 12% of 13L vinegar A and 70% of 9L vinegar B
13L of vinegar A will contain 13 * 12% = 13 * 0.12 = 1.56
9L of 70% vinegar B will contain 9 * 70% = 9 * 0.7 = 6.3
Now, the new mixture has a total volume of 13 + 9 = 22L
The concentration of the new mixture will thus be;
(1.56 + 6.3)/22
= 0.357 and that’s approximately 0.36 or simply 36%
1) should be second option
CD→
2) None of these
Answer:
There are 8 dimes there.
Step-by-step explanation:
This question is solved used a system of equations.
I am going to say that:
x is the number of nickels.
y is the number of dimes.
19 coins
This means that x + y = 19.
A nickel is worth $0.05. A dime is worth $0.1. The total of these coins is $1.35. So
0.05x + 0.1y = 1.35
How many dimes are there?
We have to find y.
From the first equation: x = 19 - y.
Replacing in the second:
0.05(19 - y) + 0.1y = 1.35
0.95 - 0.05y + 0.1y = 1.35
0.05y = 0.4
y = 0.4/0.05
y = 8
There are 8 dimes there.
X+y=43
x-y=19
2x=62
x=31
y=12
Hope this helps!
