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Artyom0805 [142]

3 years ago

5

In a class test, +4 marks were awarded for the correct answers and -1 mark for the wrong answers. Student scores 40 marks. If hi

s correct answers were 11, find his wrong answers.

1 answer:

nikklg [1K]3 years ago

7 0

Step-by-step explanation:

Let <em>y</em> the number of wrong answers got.

$11( + 4) + ( - 1)y = 40 \\ 44 - y = 40 \\ - y = - 4 \\ y = 4$

∴ He got 4 wrong answers.

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A random sample of 1000 registered voters in Flagstaff found 760 registered voters who support immigration reform. Find a 95% co

dusya [7]

Answer: $(0.7335,\ 0.7865)$

Step-by-step explanation:

Given : A random sample of 1000 registered voters in Flagstaff found 760 registered voters who support immigration reform.

sample size : n= 1000

sample proportion: $\hat{p}=\dfrac{760}{1000}=0.76$

Critical value for 95% confidence interval = $z_{\alpha/2}=1.96$

Confidence interval :

$\hat{p}\pm z_{\alpha/2}\sqrt{\dfrac{\hat{p}(1-\hat{p})}{n}}\\\\=0.76\pm(1.96)\sqrt{\dfrac{0.76(1-0.76)}{1000}}\\\\=0.76\pm0.0264708866493\\\\\approx0.76\pm0.0265\\\\=(0.76-0.0265,\ 0.76+0.0265)=(0.7335,\ 0.7865)$

Hence, the 95% confidence interval for the true percent of registered voters in Flagstaff who support immigration reform: $(0.7335,\ 0.7865)$

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3 years ago

1 3/5 divided by 2/5

madreJ [45]

Answer:

4

Step-by-step explanation:

1 3/5 ÷ 2/5

Change the mixed number to an improper fraction

( 5*1+3)/5 ÷ 2/5

8/5 ÷ 2/5

Copy dot flip

8/5 * 5/2

Rewriting

8/2 * 5/5

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3 years ago

The owner of a garden center pays $12 for each birdbath. She sells them for 55% more than she paid. Decide whether each expressi

velikii [3]

Answer:

$Selling\ Price = 12b(1.55)$

Step-by-step explanation:

Given

$Cost\ Price = \$12$

$Selling\ Price = 55\%\ more$

Required

Write an expression for the selling price for b birdbaths

This selling price for 1 birdbath is calculated as:

$Selling\ Price = Cost\ Price + 55\% * Cost\ Price$

Substitute 12 for Cost Price

$Selling\ Price = 12 + 55\% * 12$

Factorize:

$Selling\ Price = 12(1 + 55\%)$

Express percentage as decimal

$Selling\ Price = 12(1 + 0.55)$

$Selling\ Price = 12(1.55)$

For b birdbaths, the selling price is:

$Selling\ Price = 12(1.55) * b$

$Selling\ Price = 12b(1.55)$

<em>The options are not clear; However </em> $12b(1.55)$ <em> answers the question.</em>

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3 years ago

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coldgirl [10]

The car would’ve travelled 60m because 5*12=60

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3 years ago

Bill deposits $500 into an account that pays simple interest at a rate 6% per year. How much will he be paid in the first 5 year

KATRIN_1 [288]

The answer is A=$650

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More specific to this problem:
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3 years ago

Read 2 more answers