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Dennis_Churaev [7]
2 years ago
8

Four sisters bought a present for their mother. They received a 10% discount on the original price of the gift. After the discou

nt was taken, each sister payed $9. What was the original price of the gift
Mathematics
1 answer:
Orlov [11]2 years ago
4 0

Answer:

$40

Step-by-step explanation:

x is the original price of the gift

(10% of x) is the value of the discount

(10% of x) = 10/100 . x = 0.1 x

0.1 x    is the value of the discount

x - (10% of x) is what was paid, after the discount

x - 0.1 x = 0.9 x

0.9 x    is what was paid

4 children paid $9/each

4 times $9 = $36

$36 is the total amount that was paid by the children

$36 = 0.9 x

$36 / 0.9 = x

x = $36 / 0.9 = 360 / 9

x = 40

;-)

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B.

Test to see if the equations have solutions;

(3x+4y=5)--------multiply by 6

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For option D;

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Leona [35]

Answer:

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Step-by-step explanation:

Data given

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   1                 330               33                      8

   2                310                31                       7

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\sigma_{2}=7 represent the population standard deviation for 2  

n_{1}=330 sample size for the group 1  

n_{2}=310 sample size for the group 2  

\alpha Significance level provided  

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Concepts and formulas to use  

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With the info given we can replace in formula (1) like this:  

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2 years ago
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Igoryamba

Answer:

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as we have explained that the two triangles are not congruent then it's sides and angles also can't be congruent so, option 3 is also incorrect.

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ΔXYZ  was reflected over a vertical line and then dilated so the resulting ΔX'Y'Z' is similar to ΔXYZ.

i.e., △XYZ ~ △X'Y'Z'.

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2 years ago
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