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3 years ago

Lowell bought 4 1/4 pounds of apples and 3 3/5 pounds of oranges. How many pounds of fruit did Lowell boy?

Mathematics

2 answers:

Serjik [45]3 years ago

8 0

7 17/20

You add the fractions together and then simplify the answer

Zolol [24]3 years ago

6 0

$\bf 4\frac{1}{4}\implies \cfrac{4\cdot 4+1}{4}\implies \cfrac{9}{4}
\\\\\\
3\frac{3}{5}\implies \cfrac{3\cdot 5+3}{5}\implies \cfrac{18}{5}\\\\
-------------------------------\\\\
\cfrac{9}{4}+\cfrac{18}{5}\impliedby \textit{we'll use the LCD of 20}\implies \cfrac{(5\cdot 9)~+~(4\cdot 18)}{20}
\\\\\\
\cfrac{45+72}{20}\implies \cfrac{117}{20}\implies 5\frac{17}{20}$

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PLEASE HELP ME WITH MY MATH

Alina [70]

Answer:

Step-by-step explanation:

y is 3 times more than x.

X=0 Y=0 3x0=0

X=1 Y=3

X=2 Y=6

X=3 Y=9

X=4 Y=12

Then just plot it as co-ordinates (x,y)

Y is 1/4 of x. Divide by 4

X=0 Y=0

X=4 Y=1

X=8 Y=2

X=12 Y=3

X=16 Y=4

Then just plot it as co-ordinates (x,y)

8 0

2 years ago

Rachel and her friends are making necklaces out of beads and straws. They plan to use 12 beads and 5 straws for each necklace. T

bagirrra123 [75]

Answer:

225 necklaces.

Step-by-step explanation:

Assuming that they have the necessary amount of straws to match the beads then we can use the following simple equation to solve this problem.

t = b/12 ... where t is the total amount of necklaces and b is the number of beads you have

t = 2700 / 12

225 necklaces.

For 225 necklaces you would also need 1125 straws since each necklace requires 5 straws to be fully made. Therefore if you have this amount you should not run into any problems.

3 0

3 years ago

Modern medical practice tells us not to encourage babies to become too fat. Is there a positive correlation between the weight x

Anna11 [10]

Answer:

a) Figure attached

b) $y=1.31 x +98.57$

c) The correlation coefficient would be r =0.47719

d) $y=1.31 x +98.57=1.31*21 + 98.57 =126.08$

Step-by-step explanation:

(a) Draw a scatter diagram for the data.

See the figure attached

(b) Find x, y, b, and the equation of the least-squares line. (Round your answers to three decimal places.) x =__ y =__ b =__ y =__ + __x

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

With these we can find the sums:

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}=6576-\frac{300^2}{14}=147.429$

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i){n}}=38186-\frac{300*1773}{14}=193.143$

And the slope would be:

$m=\frac{193.143}{147.429}=1.31$

Nowe we can find the means for x and y like this:

$\bar x= \frac{\sum x_i}{n}=\frac{300}{14}=21.429$

$\bar y= \frac{\sum y_i}{n}=\frac{1773}{14}=126.643$

And we can find the intercept using this:

$b=\bar y -m \bar x=126.643-(1.31*21.429)=98.571$

So the line would be given by:

$y=1.31 x +98.57$

(c) Find the sample correlation coefficient r and the coefficient of determination r?2. (Round your answers to three decimal places.)

n=14 $\sum x = 300, \sum y = 1773, \sum xy=38186, \sum x^2 =6576, \sum y^2 =225649$

And in order to calculate the correlation coefficient we can use this formula:

$r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}$

$r=\frac{14(38186)-(300)(1773)}{\sqrt{[14(6576) -(300)^2][14(225649) -(1773)^2]}}=0.9534$

So then the correlation coefficient would be r =0.47719

What percentage of variation in y is explained by the least-squares model? (Round your answer to one decimal place.)

The % of variation is given by the determination coefficient given by $r^2$ and on this case $0.47719^2 =0.2277$ , so then the % of variation explaines is 22.8%.

(d) If a female baby weighs 21 pounds at 1 year, what do you predict she will weigh at 30 years of age? (Round your answer to two decimal places.) ___ lb

So we can replace in the linear model like this:

$y=1.31 x +98.57=1.31*21 + 98.57 =126.08$