Helllooo pls help me

Create a system if equations to solve this.

First equation:
25m + 24e = 220

Second equation:
m + e = 9

Then you must solve the second equation for a variable.

Change m + e = 9 to e = 9 - m.

Then substitute (9 - m) for e in the first equation.

So 25m +24e = 220 becomes 25m + 24(9 - m) = 220.

Now you can solve the first equation because the only variable in it is m.

25m + 24(9 - m) = 220 (Original equation)
25m + 216 - 24m = 220 (Distribute)
m + 216 = 220 (Combine like terms)
m = 4 (Simplify)

Now plug in 4 for m in the second equation.

m + e = 9 (Original equation)
(4) + e = 9 (Substitute)
e = 5 (Simplify)

m represents Math Books and e represents English Books, so Nicole purchased 4 Math Books and 5 English Books.

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2 years ago

An amusement park would like to determine if they want to add in a new roller coaster. In order to decide whether or not they sh

Rzqust [24]

Using the z-distribution, it is found that the 90% confidence interval is given by: (0.6350, 0.6984).

<h3>What is a confidence interval of proportions?</h3>

A confidence interval of proportions is given by:

$\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which:

$\pi$ is the sample proportion.

z is the critical value.

n is the sample size.

In this problem, we have a 90% confidence level, hence $\alpha = 0.9$ , z is the value of Z that has a p-value of $\frac{1+0.9}{2} = 0.95$ , so the critical value is z = 1.645.