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3 years ago

Please help! 10 ∑ 2i-9 i=3

1 answer:

6 0

$\sum\limits_{i=3}^{10}(2i-9)=2(3)-9+2(4)-9+2(5)-9+2(6)-9+2(7)-9\\\\+2(8)-9+2(9)-9+2(10)-9\\\\=6-9+8-9+10-9+12-9+14-9+16-9+18-9+20-9\\\\=90-72=18$

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The wholesale price for a pair of shoes is $3.50. A certain department store marks up the wholesale price by 60%. Find the price

Harrizon [31]

Answer:

Step-by-step explanation:

markup is 3.50(0.60) = $2.10

sales price is 3.50 + 2.10 = $5.60

one could also just multiply the wholesale price by 1.60

3.50(1.60) = $ 5.60

8 0

1 year ago

on a scale drawing, 5 metres is represented by 4 centimetres. write the scale as a ratio in it's simplest form.

ryzh [129]

Answer:

The scale factor is 1:125

Step-by-step explanation:

Scaling

Objects can be represented in a reduced or augmented size by using scaling which consists of multiplying or dividing by a constant factor. We use scaling when representing geographic locations on a map.

On a scale drawing, a distance of 5 meters = 500 cm is represented by 4 centimeters. The scale factor is usually represented as a ratio of the smallest to the biggest magnitude:

$\frac{4}{500}=\frac{1}{125}$

The scale factor is 1:125

8 0

3 years ago

1. 4x + 3(x-9) = 19

Dmitry_Shevchenko [17]

1) 4x + 3(x-9) = 19

or, 4x + 3x - 27 = 19

or, 7x = 19+27

or, 7x = 46

or, x = 46/7

◆ x = 6.57

2) 2(x-4) + 5x = 3

or, 2x - 8 + 5x = 3

or, 7x = 3+8

or, x = 11/7

◆ x = 1.57

3) 60 = 8y - 3(y-10)

or, 60 = 8y - 3y + 30

or, 60 - 30 = 5y

or, y = 30/5

◆ y = 6

4) 40 + 3c = 3 + 9(c-2)

or, 40 + 3c = 3 + 9c - 18

or, 40 + 3c = 9c - 15

or, 9c - 3c = 40 + 15

or, 6c = 55

◆ c = 9.166

I hope you understand..

Thank you...♥♥

5 0

2 years ago

Read 2 more answers

Amy and Ben share £21 between them in the ratio 5 : 2. How much does Amy get?

Alika [10]

Answer:

✑ $\underline{ \underline{ \sf{First ,\: Let's \: learn \: about \: the \: ratio}}} :$

Let us consider , there are 30 boys and 40 girls in a school. So, the ratio of number of boys to number of girls = $\sf{ \frac{30}{40} = \frac{3}{4} = 3:4}$ and read as 3 is to 4. We can say , the ratio compares two of more quantities of same unit. Until two quantities have same units , it is meaningless to compare by ratio. So, to find the ratio of two quantities , it is necessary to express them in same unit or of same kind. Since , they are in division form. So ,ratio is unit less quantity. Thus , the ratio is a comparison of two quantities of the same kind in division which doesn't have any units. For example : $\sf{ \frac{a}{b}}$ is a ratio and is read as ' a is to b ' in which ' a : is antecedent and ' b ' is called consequent.