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3 years ago

Multiply using mental math 50×28

Mathematics

2 answers:

alukav5142 [94]3 years ago

3 0

I believe that would be 1,400

AnnZ [28]3 years ago

3 0

The answer would be 1,400.

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* There are five cars in line at a stoplight. Each of these cars is a different color and different type of car. Diego is drivin

Svetach [21]

Info given :
vehicles : (colors)red car, green car, yellow car, blue car, white car
types : sedan, minivan, SUV, convertible, pick-up truck
people : Diego, Ingrid, Rachel, Anton, Yuna

Diego -- red car -- minivan -- 3rd car
Ingrid -- white car -- sedan -- 4th car
Yuna -- green car -- truck -- 5th car
Rachel -- yellow car -- SUV -- 1st car
Anton -- blue car -- convertible -- 2nd car

I am thinking the truck, it is green, is driven by Yuna

6 0

3 years ago

How to solve this question

VMariaS [17]

The variance method is as follows.

-Sum the squares of the values in data set, and then divide by the number of values in data set
- From that, subtract the square of the mean (add all values and divide by number of values in the data set)

Our variance is

 $\displaystyle\sigma^2 = \frac{2^2 + 5^2 + m^2}{3} - \left(\frac{2 + 5 + m}{3}\right)^2$

Since variance has to be 14, we set $\sigma^2 = 14$ and solve for m

$14= \frac{4 + 25 + m^2}{3} - \left(\frac{7 + m}{3}\right)^2\ \Rightarrow \\ \\
14 = \frac{29}{3} + \frac{1}{3}m^2 - \frac{1}{9}(7+m)^2 \\ \\
14 = \frac{29}{3}+ \frac{1}{3}m^2 - \frac{1}{9}(49 + 14m + m^2) \\ \\
14 = \frac{29}{3}+ \frac{1}{3}m^2 - \frac{49}{9}- \frac{14}{9}m- \frac{1}{9}m^2 \\ \\
0 = \frac{-88}{9} -\frac{14}{9}m + \frac{2}{9}m^2
$

quadratic formula

$m = \displaystyle\frac{-b \pm \sqrt{b^2 -4ac}}{2a} \\
m = \frac{-(-\frac{14}{9}) \pm \sqrt{\left(-\frac{14}{9}\right)^2 - 4(2/9)(-88/9)} }{2(2/9)} \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{196}{81} + \frac{704}{81} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{900}{81} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \sqrt{ \frac{100}{9} } }{\frac{4}{9} } \\
m = \frac{\frac{14}{9} \pm \frac{10}{3} }{\frac{4}{9} } \\
m = 11, -4$

-4 doesnt' work as it is not a positive integer

m = 11

5 0

3 years ago

Simplify. √-121+ √-25

astra-53 [7]

Answer:

6i

Step-by-step explanation:

sqrt(-121) - sqrt(-25)

11i - 5i

6i

8 0

3 years ago

Express as a fraction or mixed number 1.5%

Svetlanka [38]

Answer:

3/2 g.oogle if you want the explanation of your work.

4 0

3 years ago

A square garden has a side length of 11 meters. What is the area of the garden? What is the perimeter?

Talja [164]

Answer:

Area of the garden=121 square meter

perimeter of the garden=44 meter

Step-by-step explanation:

Area of a square=side*side

=11*11

=121square meter

Perimeter of a square garden=side*4

=11*4

=44 m

6 0

3 years ago

Read 2 more answers