john bought a bicycle for $20 sold it for $30 rebought it for $40 and resold it for $50. How much money did he make or loose?

31x-4+120 =180 <br> How would I solve ?<br> Any tips ?

KIM [24]

Answer:

x=64/31

Step-by-step explanation:

31x-4+120=180

31x+116=180

subtract 116 from both sides

Simplify

Divide both sides of the equation by the same term

get answer x=64/31

5 0

3 years ago

REALLY NEED HELP!!!<br> see picture*****

vladimir1956 [14]

Answer:

11) $r=4$

12) $z_3+z_1=A$

13a) $\bar z_1=3-2i$ and $\bar z_2=-5+3i$

13b) $\bar {z_1z_2}=-9-19i$

Step-by-step explanation:

11. The given equation in rectangular coordinates is $x^2+y^2=16$

To convert to polar form, use the relation $x^2+y^2=r^2$

This implies that:

$\implies r^2=16$

$r=\sqrt{16}$

$r=4$

In polar coordinates, $r=4$ is a circle with radius 4 units.

12. From the diagram;

$z_3=-3-3i$

$z_2=1+i$

$z_1=4+i$

$A=1-2i$

We can see that two arrows are moving in anticlockwise direction to meet A which is moving in the clockwise direction;

$\implies (-3-3i)+(4+i)=1-2i$

$\therefore z_3+z_1=A$

13. The conjugate of the complex number: $z=a+bi$ is $\bar z=a-bi$

Part a) The given complex numbers are:

$z_1=3+2i$ and $z_2=-5-3i$

The conjugates of these complex numbers are:

$\bar z_1=3-2i$ and $\bar z_2=-5+3i$

Part b) The product of $z_1=3+2i$ and $z_2=-5-3i$ is

$z_1z_2=(3+2i)(-5-3i)$

$z_1z_2=-15-9i-10i-6i^2$

$z_1z_2=-9-19i$

The conjugate of the product is:

$\bar {z_1z_2}=-9-19i$

5 0

3 years ago

Mopeds (small motorcycles with an engine capacity below 50 cm3) are very popular in Europe because of their mobility, ease of op

Mashcka [7]

Answer:

a) P(X<50)=0.9827

b) P(X>47)=0.4321

c) P(-1.5<z<1.5)=0.8664

Step-by-step explanation:

We will calculate the probability based on a random sample of one moped out of the population, normally distributed with mean 46.7 and standard deviation 1.75.

a) This means we have to calculate P(x<50).

We will calculate the z-score and then calculate the probability accordign to the standard normal distribution:

$z=\dfrac{X-\mu}{\sigma}=\dfrac{50-46.7}{1.75}=\dfrac{3.7}{1.75}=2.114\\\\\\P(X$

b) We have to calculatee P(x>47).

We will calculate the z-score and then calculate the probability accordign to the standard normal distribution:

$z=\dfrac{X-\mu}{\sigma}=\dfrac{47-46.7}{1.75}=\dfrac{0.3}{1.75}=0.171\\\\\\P(X>47)=P(z>0.171)=0.4321$

c) If the value differs 1.5 standard deviations from the mean value, we have a z-score of z=1.5

$z=\dfrac{(\mu+1.5\sigma)-\mu}{\sigma}=\dfrac{1.5\sigma}{\sigma}=1.5$

So the probability that maximum speed differs from the mean value by at most 1.5 standard deviations is P(-1.5<z<1.5):

$P(-1.5$

3 0

3 years ago

What is fifty five hundredths plus twenty five hundredths

Maksim231197 [3]

That would be 8000.. hope it helps

6 0

3 years ago

Read 2 more answers

Write an equation in standard form of the parabola that has the same shape as the graph of f(x)=5x^2or g(x)=-5x^2, but with a gi

pickupchik [31]

F(x)=5x^2 Has minimum (0,0)

g(x) = f(x) + 2 Shifts the graph two units up, then the minimum is 2+0=2.

h(x) = g(x+4) Shifts the graph four units left, then the minimum is at 0-4 = -4.

Then h(x) = 5(x+4)^2 + 2 has the minimum (-4,2)

And p(x) = -5(x+4)^2 + 2 has the maximum (-4,2)

4 0

3 years ago