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Juliette [100K]

3 years ago

8

ted is twice his sister's age and three years younger than joe. ted's sister is half of a century plus ten. how old is ted how o

ld is ted's sister

1 answer:

Alex17521 [72]3 years ago

4 0

Answer:

teds sister is 60 years old, ted is 120 some how, and joe is 123.

Step-by-step explanation:

half of a century is 50 because a century is 100 years and plus 10 years equals 60 and 60 times 60 equals 120 and 120 plus 3 years equals 123 so that's how I got the answers. At first this answer looks complicated you just have to read the question carefully.

You might be interested in

What is the greatest common factor of 36x^3 and 8x

marusya05 [52]

Factor 36x^3 = (2)(2)(3)(3)(x)(x)(x)
Factor 8x = (2)(2)(2)(x)

Take what they have in common which is (2)(2)(x) and multiply and it will be 4x.

6 0

4 years ago

It took my question down twice here's a real math question I guess

aliina [53]

Answer:

$n-3$

Interval notation: $(-\infty, -10)\cup(-3,\infty)$

Step-by-step explanation:

<u>First inequality:</u>

<u /> $n+8$

Therefore, this inequality restricts:

$n \in \mathrm{R};\: n$

<u>Second inequality:</u>

$< 8+n-3$

Therefore, this inequality restricts:

$n \in \mathrm{R};\: n>-3$

Therefore, with both of these restrictions together, we have:

$\fbox{$n \in \mathrm{R}; n-3$}\\\mathrm{or\:}\fbox{$n-3$}\\\mathrm{or\:}\fbox{$(-\infty, -10)\cup(-3,\infty)$}$ .

4 0

3 years ago

A physical therapist wants to determine the difference in the proportion of men and women who participate in regular sustained p

Alekssandra [29.7K]

Using the z-distribution and the formula for the margin of error, it is found that:

a) A sample size of 54 is needed.

b) A sample size of 752 is needed.

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level of $\alpha$ , we have the following confidence interval of proportions.

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

In which z is the z-score that has a p-value of $\frac{1+\alpha}{2}$ .

The margin of error is of:

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

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 $z = 1.645$ .

Item a:

The estimate is $\pi = 0.213 - 0.195 = 0.018$ .

The sample size is <u>n for which M = 0.03</u>, hence:

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

$0.03 = 1.645\sqrt{\frac{0.018(0.982)}{n}}$

$0.03\sqrt{n} = 1.645\sqrt{0.018(0.982)}$

$\sqrt{n} = \frac{1.645\sqrt{0.018(0.982)}}{0.03}$

$(\sqrt{n})^2 = \left(\frac{1.645\sqrt{0.018(0.982)}}{0.03}\right)^2$

$n = 53.1$

Rounding up, a sample size of 54 is needed.

Item b:

No prior estimate, hence $\pi = 0.05$

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

$0.03 = 1.645\sqrt{\frac{0.5(0.5)}{n}}$

$0.03\sqrt{n} = 1.645\sqrt{0.5(0.5)}$

$\sqrt{n} = \frac{1.645\sqrt{0.5(0.5)}}{0.03}$

$(\sqrt{n})^2 = \left(\frac{1.645\sqrt{0.5(0.5)}}{0.03}\right)^2$

$n = 751.7$

Rounding up, a sample of 752 should be taken.

A similar problem is given at brainly.com/question/25694087

5 0

3 years ago

Can someone smart help me here?

V125BC [204]

The answer is 573

S is the three digit number.
h - a number of hundreds
t - a number of tens
o - a number of ones

S = 100h + 10t + o

<span>The last two digits add to make ten: t + o = 10
</span><span>The first and last digits add to make eight: h + o = 8
</span><span>The first two digits add to make twelve: h + t = 12

</span>t + o = 10 ⇒ o = 10 - t
h + o = 8 ⇒ o = 8 - h
_______
10 - t = 8 - h
h + t = 12 ⇒ h = 12 - t
_______
10 - t = 8 - (12 - t)
10 - t = 8 - 12 + t
10 - t = -4 + t
10 + 4 = t + t
2t = 14
t = 14/2 = 7
______

h = 12 - t = 12 - 7 = 5
______

o = 8 - h = 8 - 5 = 3

S = 100h + 10t + o
h = 5
t = 7
o = 3

S = 100*5 + 10*7 + 3
= 500 + 70 + 3
= 573

8 0

3 years ago

Solve the quadratic equation.<br> 2x2 + 35 = 17x

atroni [7]

Get it to equal 0

minus 17x from both sides

2x²-17x+35=0

tricky part
get something like
(2x-a)(x-b)
we know the signs are negative since the middle term is negative and last term is positive

so a and b are either 1 and 35 or 5 and 7

(2x-1)(x-35), nope
(2x-35)(x-1) nope
(2x-5)(x-7), nope
(2x-7)(x-5), yep

(2x-7)(x-5)=0
set to zero
2x-7=0
2x=7
x=7/2

x-5=0
x=5

x=7/2 and 5

8 0

3 years ago