Answer:
-23
Step-by-step explanation: You have to combine like terms first:
-3.8x -5.9x =223.1
-9.7x = 223.1
Then divide om each side of the equation by -9.7.
-9.7x/-9.7 = 223.1/-9.7
x =- 23
No, there is significant difference in the use of e readers by different age groups.
Given sample 1 ( 29 years old)
=628,
=7%, sample 2( 30 years old)
=2309,
=0.11.
We have to first form hypothesis one null hypothesis and other alternate hypothesis.
π1-π2=0
π1-π2≠0
α=0.05
Difference between proportions 

The pooled proportion needed to calculate standard error is:

=(44+254)/(628+2309)
=0.10146
The estimated standard error of difference between means is computed using the formula:

=
=
=
=0.01315
Z= Pd-(π1-π2)/
=-0.04-0/0.013
=-3.0769
This test is a two tailed test so the p value for this test is calculated as (using z table)
p value:2 P(Z<-3.0769)
=2*0.002092
=0.004189
P value< significance level of 5%.
Hence there is enough evidence to show the claim that there is a significant difference in the use of e readers by different age groups.
Learn more about hypothesis at brainly.com/question/11555274
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Question is incomplete as it also includes:
Significance level of 5%.
Answer:
2 - x
Step-by-step explanation:
Add together any numbers that need to be together
5 - 2x - 3 + x
2 - x
Let me know if you need more of an explanation