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4 years ago

Find the solution set for the system of equations. 9x + 5y = 28 5x + 9y = 56

1 answer:

6 0

First step find a common multiple, e.g. 45 and subtract
9x + 5y = 28 * 5
5x + 9y = 56 * 9

45x + 25y = 140
-(45x + 81y = 504)
-56y = -364
56y = 364
y = 6.5

Substitute into any equation
9x + 5(6.5) = 28
9x + 32.5 = 28
9x = -4.5
x = -0.5

x = -0.5 , y = 6.5

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596 divided by 3 using long divison

Basile [38]

Answer:

198.6 with the remaining 6

Step-by-step explanation:

596/3

596/3 = 198.666666667 as a decimal form

596/3 = 198.67 in 2 decimal places

596/3 = 198.7 to the nearest tenth

596/3 = 198.67 to the nearest hundredth

596/3 = 198.667 to the nearest thousandth

3 0

3 years ago

To mix a particular shade of purple paint, read paint and blue paint are mixed in the ratio 5:3. To make 80 gallons of this shad

zubka84 [21]

Answer:

50 gallons of red

30 gallons of blue

Step-by-step explanation:

5 parts of the whole must be red, 3 parts of the whole must be blue, and there are 5+3=8 parts in total.

therefore, 1 part = 80/8 = 10 gallons

red : 5 parts

5×10 = 50 gallons

blue : 3 parts

3×10 = 30 gallons

4 0

3 years ago

Evaluate -5g - 6 for g = -2

Feliz [49]

Plug in g equals -5 x -2 which equals 10 because 2 negatives are a positive then 10-6 equals 4

The anwser is 4

4 0

4 years ago

Read 2 more answers

Ivana works at a department store selling perfume and makeup. She earns $375 per week and 4% commission on her sales. If Ivana's

Aleks04 [339]

Answer:

Step-by-step explanation:

Step one:

given data

weekly earnings= $375

Commission is 4% of sales.= 0.4

supposing sale is x, and the total earning is y

the expression for the total earning will be

y=375+0.4x

Step two:

for x= 2513, y will be

y=375+0.4(2513)

y=375+1005.2

y=1380.2

<em><u>Hence her total earnings for the week will be $1380.2</u></em>

3 0

3 years ago

You have a large jar that initially contains 30 red marbles and 20 blue marbles. We also have a large supply of extra marbles of

Dima020 [189]

Answer:

There is a 57.68% probability that this last marble is red.

There is a 20.78% probability that we actually drew the same marble all four times.

Step-by-step explanation:

Initially, there are 50 marbles, of which:

30 are red

20 are blue

Any time a red marble is drawn:

The marble is placed back, and another three red marbles are added

Any time a blue marble is drawn

The marble is placed back, and another five blue marbles are added.

The first three marbles can have the following combinations:

R - R - R

R - R - B

R - B - R

R - B - B

B - R - R

B - R - B

B - B - R

B - B - B

Now, for each case, we have to find the probability that the last marble is red. So

$P = P_{1} + P_{2} + P_{3} + P_{4} + P_{5} + P_{6} + P_{7} + P_{8}$

$P_{1}$ is the probability that we go R - R - R - R

There are 50 marbles, of which 30 are red. So, the probability of the first marble sorted being red is $\frac{30}{50} = \frac{3}{5}$ .

Now the red marble is returned to the bag, and another 3 red marbles are added.

Now there are 53 marbles, of which 33 are red. So, when the first marble sorted is red, the probability that the second is also red is $\frac{33}{53}$

Again, the red marble is returned to the bag, and another 3 red marbles are added

Now there are 56 marbles, of which 36 are red. So, in this sequence, the probability of the third marble sorted being red is $\frac{36}{56}$

Again, the red marble sorted is returned, and another 3 are added.

Now there are 59 marbles, of which 39 are red. So, in this sequence, the probability of the fourth marble sorted being red is $\frac{39}{59}$ . So

$P_{1} = \frac{3}{5}*\frac{33}{53}*\frac{36}{56}*\frac{39}{59} = \frac{138996}{875560} = 0.1588$

$P_{2}$ is the probability that we go R - R - B - R

$P_{2} = \frac{3}{5}*\frac{33}{53}*\frac{20}{56}*\frac{36}{61} = \frac{71280}{905240} = 0.0788$

$P_{3}$ is the probability that we go R - B - R - R

$P_{3} = \frac{3}{5}*\frac{20}{53}*\frac{33}{58}*\frac{36}{61} = \frac{71280}{937570} = 0.076$

$P_{4}$ is the probability that we go R - B - B - R

$P_{4} = \frac{3}{5}*\frac{20}{53}*\frac{25}{58}*\frac{33}{63} = \frac{49500}{968310} = 0.0511$

$P_{5}$ is the probability that we go B - R - R - R

$P_{5} = \frac{2}{5}*\frac{30}{55}*\frac{33}{58}*\frac{36}{61} = \frac{71280}{972950} = 0.0733$

$P_{6}$ is the probability that we go B - R - B - R

$P_{6} = \frac{2}{5}*\frac{30}{55}*\frac{25}{58}*\frac{33}{63} = \frac{49500}{1004850} = 0.0493$

$P_{7}$ is the probability that we go B - B - R - R

$P_{7} = \frac{2}{5}*\frac{25}{55}*\frac{1}{2}*\frac{33}{63} = \frac{825}{17325} = 0.0476$

$P_{8}$ is the probability that we go B - B - B - R

$P_{8} = \frac{2}{5}*\frac{25}{55}*\frac{1}{2}*\frac{30}{65} = \frac{750}{17875} = 0.0419$

So, the probability that this last marble is red is:

$P = P_{1} + P_{2} + P_{3} + P_{4} + P_{5} + P_{6} + P_{7} + P_{8} = 0.1588 + 0.0788 + 0.076 + 0.0511 + 0.0733 + 0.0493 + 0.0476 + 0.0419 = 0.5768$

There is a 57.68% probability that this last marble is red.

What's the probability that we actually drew the same marble all four times?

$P = P_{1} + P_{2}$

$P_{1}$ is the probability that we go R-R-R-R. It is the same $P_{1}$ from the previous item(the last marble being red). So $P_{1} = 0.1588$

$P_{2}$ is the probability that we go B-B-B-B. It is almost the same as $P_{8}$ in the previous exercise. The lone difference is that for the last marble we want it to be blue. There are 65 marbles, 35 of which are blue.

$P_{2} = \frac{2}{5}*\frac{25}{55}*\frac{1}{2}*\frac{35}{65} = \frac{875}{17875} = 0.0490$

$P = P_{1} + P_{2} = 0.1588 + 0.0490 = 0.2078$

There is a 20.78% probability that we actually drew the same marble all four times

3 0

3 years ago