Let
x = number of liters of the 40% salt solution
y = number of liters of the 20% salt solution
The two amounts (x and y) must combine to 1500 liters, so
x+y = 1500
we can solve for y to get
y = 1500-x
after subtracting x from both sides
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If we have x liters of the 40% salt solution (composed of pure salt plus other stuff) then we have exactly 0.40*x liters of pure salt. Simply multiply the decimal form of the percentage with the amount of solution.
Similarly, if we have y liters of the 20% solution, then we have 0.20*y liters of pure salt
Combined, we have 0.40*x + 0.20*y liters of pure salt all together.
We want 1500 liters of a 28% solution, so we want 1500*0.28 = 420 liters of pure salt
Equate the two expressions (0.40*x + 0.20*y and 420) to get
0.40*x + 0.20*y = 420
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We have the equation 0.40*x + 0.20*y = 420 and we also know that y = 1500-x
Let's use the substitution property now
0.40*x + 0.20*y = 420
0.40*x + 0.20*( y ) = 420
0.40*x + 0.20*( 1500 - x ) = 420 ... note how y is replaced with 1500-x
Now we can solve for x
0.40*x + 0.20*( 1500 - x ) = 420
0.40*x + 0.20*(1500) + 0.20*(-x) = 420
0.40*x + 300 - 0.20x = 420
0.40*x - 0.20x + 300 = 420
0.20x + 300 = 420
0.20x + 300 - 300 = 420 - 300
0.20x = 120
0.20x/0.20 = 120/0.20
x = 600
Now that we know x, use this to find y
y = 1500-x
y = 1500-600 ... plug in x = 600 (ie replace x with 600)
y = 900
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Answers:
We need 600 liters of the 40% solution
We need 900 liters of the 20% solution
Answer:
Area =22/7×12×12
=281.142cm square
Step-by-step explanation:
Answer:
129
Step-by-step explanation:
Collinear means that the points X, Y, and Z are on the same line. The question asks for one possible value of YZ, so for this, let's assume point X is between Point Y and Point Z.
This means...
XY+XZ=YZ
54+75=YZ
YZ=129
The second one
36/25
hope this helps
good luck!!! :))))
<h2><u>
Answer:</u></h2>
The <u>algebraic expressions</u> are composed of several elements: Terms, Coefficients, Signs, Variables and Exponents. In this case we will focus on the first two.
<u>The terms</u> are composed of sign, coefficient, variable and exponent. The terms are separated from each other by the plus sign (+) or the minus sign (-).
For example, in the following expression:
2x-3x
We have two terms separated by the negative sign (-):
2x is the first term
-3x is the second term
Now, <u>the coefficients</u> are the numbers that multiply the variable. <u>Note that if this coefficient is one (1) it is omitted
.</u>
For example in the following expression, the variable is x:
2x-3x+x
2 is the coefficient of x in the first term
-3 is the coefficient of x in the second term
1 is the coefficient of x in the third term, <u>but is omitted
</u>
In order to understand this in a better way, see the figure attached, where the algebraic expression is composed by one term.
