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3 years ago

8

1) if i gave 1/8 of my money to my sister and 2/3 of my money to my brother, how much money do I have left, if I started out wit

h $12?

2 answers:

andrey2020 [161]3 years ago

7 0

Answer:

$2.50

Step-by-step explanation:

Volgvan3 years ago

4 0

2.5. 1/8 of 12 is 1.5 and 2/3 of 12 is 8 and 8 plus 1.5 is 9.5.

You might be interested in

Geometry math question no Guessing and Please show work

sweet [91]

As we know that remote exterior angle can be given by

m<z=m<x+m<y

151-5n=4n-18+n+9

151+18-9=5n+4n+n

160=10n

n=16

m<z=151-5*16

m<z=151-80=71

6 0

3 years ago

Find 4 consecutive odd numbers such that twice the sum of the least 2 numbers is 40 less than three times the sum of the greates

ANTONII [103]

4 consecutive odd numbers....x, x + 2, x + 4, x + 6

2(x + x + 2) = 3(x + 4 + x + 6) - 40
2(2x + 2) = 3(2x + 10) - 40
4x + 4 = 6x + 30 - 40
4x + 4 = 6x - 10
4x - 6x = -10 - 4
-2x = - 14
x = -14/-2
x = 7

x + 2 = 7 + 2 = 9
x + 4 = 7 + 4 = 11
x + 6 = 7 + 6 = 13

ur numbers are : 7,9,11,13 <==

4 0

4 years ago

A study is conducted to determine if a newly designed text book is more helpful to learning the material than the old edition. T

CaHeK987 [17]

Answer:

We need to conduct a hypothesis in order to check if the mean is higher than 75, the system of hypothesis are :

Null hypothesis: $\mu \leq 75$

Alternative hypothesis: $\mu > 75$

A. One-Tailed

$z=\frac{82.2-75}{\frac{10.4}{\sqrt{10}}}=2.189$

$p_v =P(z>2.189)=0.0143$

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis.

Step-by-step explanation:

Data given and notation

We have the following data: 84 94 80 88 77 68 90 74 96 71

We can calculate the sample mean with the following formula:

$\bar X =\frac{\sum_{i=1}^n X_i}{n}$

And replacing we got:

$\bar X=82.2$ represent the sample mean

$\sigma=10.4$ represent the population standard deviation

$n=10$ sample size

$\mu_o =75$ represent the value that we want to test

$\alpha=0.01$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is higher than 75, the system of hypothesis are :

Null hypothesis: $\mu \leq 75$

Alternative hypothesis: $\mu > 75$

A. One-Tailed

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

Calculate the statistic

We can replace in formula (1) the info given like this:

$z=\frac{82.2-75}{\frac{10.4}{\sqrt{10}}}=2.189$

P-value

Since is a ONE-TAILED test the p value would given by:

$p_v =P(z>2.189)=0.0143$

Conclusion

If we compare the p value and the significance level given $\alpha=0.01$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis.

5 0

3 years ago

4/w - 10 = 5<br>this is 8th grade<br>

vovikov84 [41]

Answer:

4/w-10=5

One solution was found :

w = 4/15 = 0.267

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

4/w-10-(5)=0

Step by step solution :

Step 1 :

4

Simplify —

w

Equation at the end of step 1 :

4

(— - 10) - 5 = 0

w

Step 2 :

Rewriting the whole as an Equivalent Fraction :

2.1 Subtracting a whole from a fraction

Rewrite the whole as a fraction using w as the denominator :

10 10 • w

10 = —— = ——————

1 w

Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

2.2 Adding up the two equivalent fractions

Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

4 - (10 • w) 4 - 10w

———————————— = ———————

w w

Equation at the end of step 2 :

(4 - 10w)

————————— - 5 = 0

w

Step 3 :

Rewriting the whole as an Equivalent Fraction :

3.1 Subtracting a whole from a fraction

Rewrite the whole as a fraction using w as the denominator :

5 5 • w

5 = — = —————

1 w

Step 4 :

Pulling out like terms :

4.1 Pull out like factors :

4 - 10w = -2 • (5w - 2)

Adding fractions that have a common denominator :

4.2 Adding up the two equivalent fractions

-2 • (5w-2) - (5 • w) 4 - 15w

————————————————————— = ———————

w w

Equation at the end of step 4 :

4 - 15w

——————— = 0

w

Step 5 :

When a fraction equals zero :

5.1 When a fraction equals zero ...

Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

4-15w

————— • w = 0 • w

w

Now, on the left hand side, the w cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :

4-15w = 0

Solving a Single Variable Equation :

5.2 Solve : -15w+4 = 0

Subtract 4 from both sides of the equation :

-15w = -4

Multiply both sides of the equation by (-1) : 15w = 4

Divide both sides of the equation by 15:

w = 4/15 = 0.267

One solution was found :

w = 4/15 = 0.267

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

Line pq is the perpendicular bisector of line MN, what is QN?

GREYUIT [131]

We know that
if PQ <span>is the perpendicular bisector of line MN
then
MQ=QM
and
NP=MP
so
6x+1=10x-17----------> 10x-6x=17+1-----> 4x=18---------> x=18/4----> x=4.5

QN=2x+5-----> QN=2*4.5+5-----> QN=14

the answer is
QN is 14</span>

4 0

3 years ago