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3 years ago

In 20 years charles will bevthree time as old as he is now. how old is he now?

1 answer:

7 0

Answer:

10

Explanation:

Make our unknown equal to x, in this case his current age.

In 20 years he will be three times as old as he is now, in other words:

x + 20 = 3x

Now solve the equation:

20 = 3x - x
20 = 2x
10 = x

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At the chocolatier, classic chocolate fudge costs 10 dollars a pound. Anna purchases 7/9 of a pound of the fudge. The cash regis

Elina [12.6K]

Anna pays $7.78. Or not rounded 7.777777..... repeated.

Hope this helps!

8 0

3 years ago

The table shows the estimated number of bees, y, in a hive x days after a pesticide is released near the hive. Which function be

vladimir2022 [97]

Answer:

The exponential function best models the data for the given table.

Step-by-step explanation:

Given : The table showing the estimated number of bees, y, in a hive x days after a pesticide is released near the hive.

We have to find which function best models the data for the given table.

Consider the given data in the table.

We first plot the data using Expo- regression calculator (as shown in attachment)

Since, The the estimate number of bees deceases with increasing number of days ,thus the data represents an exponential decay over time.

Thus, The exponential function best models the data for the given table.

And the equation of model is given as $y=9958.3e^{-0.029x}$

Where y represents the estimate number of bees

and x represents the number of days.

8 0

3 years ago

Write three powers with whole number bases that have values greater than 120 and less than 130

vovangra [49]

Three powers with whole number bases that have values greater than 120 and less than 130 are:
11² = 11 x 11 = 121
5³ = 5 x 5 x 5 =125 
2⁷ = 2 x 2 x 2 x 2 x 2 x 2 x 2 = 128

7 0

3 years ago

A gardener is growing tomato plants. one plant starts out 5 cm tall. it grows constant 2 cm every week. which equation represent

kipiarov [429]

Answer:

$tn = 5 + (n - 1)2$

Step-by-step explanation:

hope it's correct

4 0

3 years ago

Day care centers expose children to a wider variety of germs than the children would be exposed to if they stayed at home more o

Ostrovityanka [42]

Answer:

a) The study is an observational study

b) The proportion of children with significant social activity in children with acute lymphoblastic leukemia is approximately 0.802

The proportion of children with significant social activity in children without acute lymphoblastic leukemia is approximately 0.8565

c) The odds ratio is approximately 0.6780

d) The 95% CI is approximately 0.523 < OR < 0.833

e) i) Yes

ii) Children with more social activity have a higher occurrence of acute lymphoblastic leukemia

Step-by-step explanation:

a) An experimental study is a study in which the researcher adds inputs to the study and then monitors the outcomes

An observational study is one in which the researcher observes risk factors and does not intervene in the process

Therefore, the study is an observational study

b) The proportion of children with significant social activity in children with acute lymphoblastic leukemia is $\hat p_1$ = 1020/1272 = 85/106 = $0.8\overline {0188679245283}$ ≈ 0.802

The proportion of children with significant social activity in children without acute lymphoblastic leukemia is $\hat p_2$ = 5343/6238 ≈ 0.8565

c) We have the following two way table;

$\begin{array}{ccc}Lymphoblastic \ Leukemia &With \ Social \ Activity & Without \ Social \ Activity\\With&1020 \ (a)&252 \ (b)\\Without&5343 \ (c)&895 \ (d) \end{array}$

$The \ odds \ ratio = \dfrac{1,020 \times 895}{5,343 \times 252} \approx 0.6780$

The odds ratio ≈ 0.6780

d) The 95% confidence interval for the odds ratio is given as follows;

$95 \% \ CI = OR \ \pm \ 1.96 \times \sqrt{\dfrac{1}{a} +\dfrac{1}{b}+\dfrac{1}{c}+\dfrac{1}{d}}$

Where;

a = 1020, b = 252, c = 5343, d = 895

Therefore;

$95 \% \ CI \approx 0.6780 \ \pm \ 1.96 \times \sqrt{\dfrac{1}{1,020} +\dfrac{1}{252}+\dfrac{1}{5,343}+\dfrac{1}{895}} \approx 0.678 \pm0.155$

The 95% CI ≈ 0.523 < OR < 0.833

e) i) Given that the observed Odds Ratio is within the Confidence Interval, therefore, there is an indication that the amount of social activity is associated with acute lymphoblastic leukemia

ii) Based on the proportion of the study findings, children with more social activity have a higher occurrence of acute lymphoblastic leukemia

6 0

3 years ago