The perimeter of a rectangle is 40cm. If the length were doubled and the width halved, the perimeter would be increased by 16cm.
1 answer:
Answer:
The dimensions of the original rectangle are Length =12cm, Width=8cm
Step-by-step explanation
Let the length of the rectangle be x
Let the width of the rectangle be y
The perimeter of a rectangle is 40cm.
2(x+y)=40
Divide both sides by 2
x+y=20
If the length were doubled(2x) and the width halved(y/2), the perimeter would be increased by 16cm,i.e.(40+16)cm
Therefore:
Divide both sides by 2
From the first equation, x=20-y.
Substitute x=20-y into
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Answer:
The pvalue of the test is 0.0784 > 0.01, which means that at this significance level, we do not reject the null hypothesis that the percentage of blue candies is equal to 29%.
Step-by-step explanation:
The candy company claims that the percentage of blue candies is equal to 29%.
This means that the null hypothesis is:
We want to test the hypothesis that this is true, so the alternate hypothesis is:
The test statistic is:
In which X is the sample mean, is the value tested at the null hypothesis,
is the standard deviation and n is the size of the sample.
0.29 is tested at the null hypothesis:
This means that
Suppose that in a random selection of 100 colored candies, 21% of them are blue.
This means that
Value of the test statistic:
Pvalue of the test:
The pvalue of the test is the probability of the sample proportion differing at least 0.21 - 0.29 = 0.08 from the population proportion, which is 2 multiplied by the pvalue of Z = -1.76.
Looking at the z-table, z = -1.76 has a pvalue of 0.0392
2*0.0392 = 0.0784
The pvalue of the test is 0.0784 > 0.01, which means that at this significance level, we do not reject the null hypothesis that the percentage of blue candies is equal to 29%.