All categories

3 years ago

Can some one explain and help me and answer it

Mathematics

1 answer:

brilliants [131]3 years ago

4 0

Answer

Sal spent 43 minutes jogging per day last week.

Elena spent 45 minutes jogging per day last week.

Step-by-step

Part 1: Find the number of minutes Sal jogged.

1. Find the number of minutes out of the week that were spent jogging.

240 - 25 = 215

Sal spent 215 minutes jogging.

2. Find the number of minutes per day he spent jogging.

215 / 5 = 43

Sal spent 43 minutes jogging per day last week.

Part 2: Find the number of minutes Elena jogged.

1. Find the number of minutes out of the week that were spent jogging.

300 - 15(5) = 300 - 75 = 225

Elena spent 225 minutes jogging.

2. Find the number of minutes per day she spent jogging.

225 / 5 = 45

Elena spent 45 minutes jogging per day last week.

You might be interested in

Find cos θ given that cos 2θ = 5/6 and 0 ≤ θ < π/2. Give an exact answer

trasher [3.6K]

$\bf \textit{Double Angle Identities}
\\ \quad \\
sin(2\theta)=2sin(\theta)cos(\theta)
\\ \quad \\
cos(2\theta)=
\begin{cases}
cos^2(\theta)-sin^2(\theta)\\
1-2sin^2(\theta)\\
\boxed{2cos^2(\theta)-1}
\end{cases}
\\ \quad \\
tan(2\theta)=\cfrac{2tan(\theta)}{1-tan^2(\theta)}\\\\
-------------------------------\\\\
$

$\bf cos(2\theta)=\cfrac{5}{6}\implies 2cos^2(\theta)-1=\cfrac{5}{6}\implies 2cos^2(\theta)=\cfrac{5}{6}+1
\\\\\\
2cos^2(\theta)=\cfrac{11}{6}\implies cos^2(\theta)=\cfrac{11}{12}\implies cos(\theta)=\pm\sqrt{\cfrac{11}{12}}$

now, bear in mind, the square root gives us +/- versions, so, which is it? well, we know the angle is in the range of "0 ≤ θ < π/2", that simply means the 1st quadrant, so, we'll use the positive one then

 $\bf cos(\theta)=\cfrac{\sqrt{11}}{\sqrt{12}}\implies cos(\theta)=\cfrac{\sqrt{11}}{2\sqrt{3}}
\\\\\\
\textit{now, let's rationalize the denominator}
\\\\\\
\cfrac{\sqrt{11}}{2\sqrt{3}}\cdot \cfrac{\sqrt{3}}{\sqrt{3}}\implies \cfrac{\sqrt{11}\cdot \sqrt{3}}{2\sqrt{3^2}}\implies \cfrac{\sqrt{11\cdot 33}}{2\cdot 3}\implies \boxed{\cfrac{\sqrt{33}}{6}}$

3 0

4 years ago

It is a well-known fact that 50% of the general population are rascals (P(R) = 0.5) and 50% of the general population are not ra

aleksley [76]

Answer:

The answer is D. 0.75

Step-by-step explanation:

Let call R the event that a person is rascal, RC a person is not rascal, TH a person use top hat and NTH a person don’t use top hat.

From the information on the question we have 4 options with their respective probability:

1. A person could be rascal and use top Hat: this probability is calculate as the multiplication of the probability of be a rascal (0.5) and use a top hat (0.9), then:

P(R y TH)=0.5*0.9=0.45

2. A person could be rascal and don’t use top Hat: this probability is calculate as the multiplication of the probability of be a rascal (0.5) and not use a top hat (0.9), then:

P(R y NTH)=0.5*0.1=0.05

3. A person could be not rascal and use top Hat: this probability is calculate as the multiplication of the probability of not be a rascal (0.5) and use a top hat (0.3), then:

P(RC y TH)=0.5*0.3=0.15

4. A person could be not rascal and not use top Hat: this probability is calculate as the multiplication of the probability of not be a rascal (0.5) and not use a top hat (0.7), then:

P(RC y NTH)=0.5*0.7=0.35

Then the probability that a person is a rascal given that he is wearing a top hat could be written and calculate as:

$P(R/TH)=\frac{P(R y TH)}{P(TH)}$

For calculate P(TH) we need to sum all the option in which TH is involve so:

P(TH) = P(R y TH)+ P(RC y TH)

P(TH)=0.45+0.15=0.6

Replacing values on the first equation we get:

$P(R/TH)=\frac{0.45}{0.6} =0.75$

So, the probability that a person is a rascal given that he is wearing a top hat is 0.75

5 0

4 years ago

On the grid draw a scaled copy of quadrilateral ABCD with a scale factor 2/3

Tamiku [17]

Answer:

Attached diagram A'B'C'D'

Step-by-step explanation:

Given is a quadrilateral ABCD. It says to draw a dilated version with a scale factor 2/3.

We see that scale factor is less than 1 which means it shrinks the image to a smaller one.

To draw a scaled copy, we need to find the lengths of its sides.

To do so, we can draw the diagonals AC & BD, and they intersect at origin O(0,0) such that OA= -2, OB= 2, OC= 4, OD= -4.

Applying a scale factor of 2/3, we get OA' = -4/3, OB' = 4/3, OC' = 8/3, OD' = -8/3.

So we have attached a scaled copy A'B'C'D' of quadrilateral ABCD with a scale factor 2/3.

6 0

3 years ago

Which expression below gives the average rate of change of the function g(x) = -x2 - 4x on the interval 6 ≤ x ≤ 8 ?

Paha777 [63]

Answer: -18

Explanation:

Average rate of change is slope: $\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$ . Need to find the y-coordinates:

g(x) = -x² - 4x

g(6) = -(6)² - 4(6)

= -36 - 24

= -60

⇒ (6, -60)

g(8) = -(8)² - 4(8)

= -64 - 32

= -96

⇒ (8, -96)

m = $\frac{-96 - (-60)}{8 - 6}$

= $\frac{-36}{2}$

= -18

7 0

3 years ago

Read 2 more answers

find the slope of the line and a point on the line y-4= x+5 I got that the slope is 9 correct? then how do I find a point on the

Licemer1 [7]

in order to find a point on the line assume that the line cuts the y-intercept at x=0 then subsitute this value on the equation to get the value of of y at this point x=0

4 0

4 years ago