We can use the distributive property for this:
4 (p+2) = 28
4p + 8 = 28.
4p = 28 - 8.
4p = 24.
Divide by 4 on both sides:
p = 6
If Sandra mixes <em>x</em> L of 65% solution with <em>y</em> L of 90% solution, then the resulting mixture has a total volume of
<em>x</em> + <em>y</em> = 500
litres, and it contains
0.65<em>x</em> + 0.90<em>y</em> = 0.75 (500) = 375
litres of alcohol.
Solve the first equation for <em>y</em> :
<em>y</em> = 500 - <em>x</em>
<em />
Substitute this into the second equation and solve for <em>x</em> :
0.65<em>x</em> + 0.90 (500 - <em>x</em>) = 375
0.65<em>x</em> + 450 - 0.90<em>x</em> = 375
75 = 0.25<em>x</em>
<em>x</em> = 300
Solve for <em>y</em> :
<em>y</em> = 500 - 300
<em>y</em> = 200
So, Sandra should mix 300 L of 65% solution with 200 L of 90% solution.
Answer:
15%
Step-by-step explanation:
Given,
Original price = $55.00
Discounted price = $46.75
Discount = $55.00 - $46.75 = $8.25
Percent Discount = (Discount / Original price) x 100%
= (8.25 / 55.00) x 100%
= 0.15 x 100%
= 15%
Mult. the 2nd eqn by 6 and then add this "new" equation to the 1st given eqn:
-6x + y = -2
6x -18y = 54
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-17y = 52, or y = -52/17. Subst. this value of y into either equation to find the value of x.
Answer:
no
Step-by-step explanation:
