How do you solve x-3y=7<br> 4x+2y=14

A sports club needs to raise at least $500 by selling chocolate bars for $2.50 each. Sebastian wants to know how many chocolate

mario62 [17]

Answer:

The inequality should be written as $2.50 times c is greater than or equal to c.

Step-by-step explanation:

First, identify what you know:

1) Each chocolate bar is $2.50

2) Sebastian needs to raise at least $500

So, Sebastian needs to sell at least enough chocolate bars to hit $500. The inequality cannot be written as less than or equal to, because he can't sell less than the number of chocolate bars needed to make $500.

Automatically, I can calculate the minimum number of bars he'll need to sell.

500/2.50 = 200 chocolate bars minimum

c must equal greater than or equal to $500, for Sebastian to raise enough money! So, basically Sebastian has to sell 200 bars OR more.

Hope this helps! :)

4 0

4 years ago

Read 2 more answers

jocelyn mowed a lawn that is 722 1/2 square yards. Her brother mowed a lawn that is 842 18/25 square yards. How many square yard

cricket20 [7]

Together they mowed 1565 11/50 square yards. You have to make the fractions have same denominators so you can add, after fixing the denominators, just add.

7 0

3 years ago

The principal randomly selected six students to take an aptitude test. their scores were: 81.4 78.6 71.3 77.8 76.9 77.7 determin

Firdavs [7]

The confidence interval is $77.28\pm 2.23$ .

We first find the mean. Add together all of the data points and divide by 6, the number of data points; the mean is 77.28.

Next we find the standard deviation. Find the difference between each data point and the mean; square it; find the sum; divide by the number of data points; take the square root. The standard deviation is 3.32.

To find the margin of error, we calculate the z-score associated with this level of confidence. 100-90 = 10% = 0.1; 0.1/2 = 0.05; 1-0.05 = 0.95. Using a z-table (http://www.z-table.com) we see that this is between two scores, 1.64 and 1.65; we will use 1.645.

The margin of error is given by
z * (σ/√n) = 1.645*(3.32/√6) = 2.23.

Thus the confidence interval is 77.28 +/ 2.23.

3 0

3 years ago

Help me with this and answer letters a and b

Darya [45]

Answer:

Step-by-step explanation:

a) a = 2*2.99- (2.99 +1.49)

a = 5.98 - 4.48

a = $1.50

r = 2* 3.99 - (3.99 + 2.49)

r = 7.98 - 6.48

r = $ 1.50

B) Both fruits has the same discount.

4 0

4 years ago

A quality-conscious disk manufacturer wishes to know the fraction of disks his company makes which are defective. Step 2 of 2 :

Diano4ka-milaya [45]

Answer: (0.120,0.160)

Step-by-step explanation:

Given : Sample size : $n=815$

Number of disks were not defective =701

Then , the number of disks which are defective = $815-701=114$

Now, the proportion of disks which are defective : $p=\dfrac{114}{815}\approx0.14$

Significance level : $\alpha: 1-0.9=0.1$

Critical value : $z_{\alpha/2}=1.645$

The confidence interval for population proportion is given by :-

$p\pm\ z_{\alpha/2}\sqrt{\dfrac{p(1-p)}{n}}\\\\=0.14\pm(1.645)\sqrt{\dfrac{(0.14)(1-0.14)}{815}}\\\\\approx0.14\pm0.020=(0.14-0.020,0.14+0.020)=(0.120,0.160)$

Hence, the 90% confidence interval for the population proportion of disks which are defective = (0.120,0.160)

7 0

3 years ago

How do you solve x-3y=7 4x+2y=14