The present ages of Tina and Mina are in the ratio of 4:5 if the sum of their ages after three years would be 33 years find their present age

After x half-lifes, the amount of the isotope is:

A(x*T) = 90mg*e{-x*ln(2)}

And after 70 days, there are 5.628 mg

We define the half-life as the time such that the inital amount of a given substance reduces to half of it.

If the half-life is T, the amount of the substance can be written as:

A(t) = a*e^{-λ*t}

Where λ = ln(2)/T.

and a is the initial amount.

In this case, T = 17.5 days, then:

λ = ln(2)/17.5 days = 0.0396 / day

And we also have a = 90mg

Then the exponential equation is:

A(t) = 90mg*e^{-t*0.0396 / day}

After x half-lifes, the amount of the isotope left is:

A(x*T) = 90mg*e^{-x*T*ln(2)/T} = 90mg*e^{-x*ln(2)}

And after 70 days the amount is:

A(70 days) = 90mg*e^{-70 days*0.0396 / day} = 5.628 mg

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Answer:

Y=90mg(0.5)^5

1.86 after 70 days

Step-by-step explanation:

Hey there!

1/(√2+√3)-√4

=−2−√2+√3

(Decimal: -1.682163)

Answer:

C, Almost fifty percent

Step-by-step explanation: I just got it right.

The time it will take Carley's dad to mow the lawn is 3.3 hours.

Rate is the ratio between two related quantities in different units. Therefore,

The rate Carley do the  lawn = 1 / 5

When they work together they do it the 1 / 2 rate.

Therefore,

let

the hours it takes Carley dad = x hours . Therefore,

1 / 5 + 1 / x  = 1 / 2

x + 5/ 5x = 1 / 2

cross multiply

2(x + 5) = 5x

2x + 10 = 5x

10 = 5x - 2x

10 = 3x

x = 10 / 3

x = 3.3 hours

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Answer:

x = - 3, y = - 1

Step-by-step explanation:

y = 7x + 20 -----> equation 1

4x - y = - 11

4x - ( 7x + 20 ) = - 11

4x - 7x - 20 = - 11

- 3x = - 11 + 20

- 3x = 9

x = 9 / - 3

x = - 3

Substitute x = - 3 in equation 1,

y = 7 ( - 3 ) + 20

  = - 21 + 20

y = - 1

Hence,

x = - 3

y = - 1

Answer:

Explanation:

y = 7x + 20 __ equation 1

4x - y = -11

y = 11 + 4x __ equation 2

using substitution method,

11 + 4x = 7x + 20

4x - 7x = 20 - 11

-3x = 9

x = -3

Find y,

y = 7x + 20

y = 7(-3) + 20

y = -1

First, we know that angle B is congruent to angle E.

2x + 40 = 5x + 10

2x + 30 = 5x

30 = 3x

x = 10

Angle B and Angle E = 60 degrees

Angle C = 14 degrees

Remember that the interior angles of a triangle always add up to 180 degrees. Now that we know 2 of the 3 angles of these triangles, and because they are congruent, all that's left to do is find Angle A/D by setting up a simple equation.

60 + 14 + D = 180

74 + D = 180

D = 106

Angle D = 106 degrees

Hope this helps!

Answer:

Step-by-step explanation:

<E = <A                property of congruency.

<A = 5x + 10        Comes from the fact that <A and <E are equal.

Three angles of the triangle are given. They add to 180 degrees.

2x + 40 + x + 4 + 5x + 10 = 180         Combine like terms

8x + 54 = 180                                     Subtract 54 from both sides.

8x + 54 - 54 = 180 - 54                      Combine  

8x = 126                                              Divide by 8

8x/8 = 126/8

x = 15.75

<B = <D                                               Congruency and parallel lines

<D = 2x + 40                                       Substitute for x

<D = 2*15.75  +  40                             Combine

<D = 31.5 + 40

<D = 71.5

Answer:

7 is first

2 is second

7.3 is third

Step-by-step explanation:

Answer:

see explanation

Step-by-step explanation:

the horizontal leg = 7 units

the vertical leg = 2

using Pythagoras' identity to find the distance d

d = [tex]\sqrt{7^2+2^2}[/tex] = [tex]\sqrt{49+4}[/tex] = [tex]\sqrt{53}[/tex] ≈ 7.3 ( to 1 dec. place )

Area :-

[tex]\\ \rm\rightarrowtail side^2[/tex]

[tex]\\ \rm\rightarrowtail 13^2[/tex]

[tex]\\ \rm\rightarrowtail 169[/tex]

Square root:-

Using it's concept, it is found that there is a 0.3333 = 33.33% probability that one of the numbers falling uppermost is a 5.

A probability is given by the number of desired outcomes divided by the number of total outcomes.

The outcomes are given as follows:

(1,1), (1,2), (1,3), (1,4), (1,5), (1,6)

(2,1), (2,2), (2,3), (2,4), (2,5), (2,6)

(3,1), (3,2), (3,3), (3,4), (3,5), (3,6)

(4,1), (4,2), (4,3), (4,4), (4,5), (4,6)

(5,1), (5,2), (5,3), (5,4), (5,5), (5,6)

(6,1), (6,2), (6,3), (6,4), (6,5), (6,6)

From the list, we have that:

Hence, the probability is given by:

p = 10/30 = 0.3333 = 33.33%.

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Answer:

A&C

Step-by-step explanation:

It would be A because it has 750 mL and C because it has 250mL and 750+250=1000

Also can you mark brainlyist you dont have to

Answer:

Step-by-step explanation:

Use a distributive property.

Distributive property:

[tex]\Longrightarrow:\sf{A(B+C)=AB+AC}[/tex]

⇒ 4(r+1)+3r

To multiply, first expand the form.

⇒ 4*r=4r

⇒ 4*1=4

Rewrite the problem down.

⇒ 4r+4+3r

Combine like terms.

⇒ 4r+3r+4

Solve.

Add similar to elements.

Add the numbers from left to right.

⇒ 4r+3r=7r

⇒ = 7r+4

I hope this helps you! Let me know if my answer is wrong or not.

Answer: 108, 132, 156, and 180

Step-by-step explanation:

If you need to add 24 to the first term for the next 4 terms, you would have

84 + 24 = 108

108 + 24 = 132

132 + 24 = 156

156 + 24 = 180

So your sequence would be 108, 132, 156, and 180 for the next 4 terms.

Answer:

why you delete my answer before question

Answer:

yes

Step-by-step explanation:

because the hypotenus is the longest of all the other sizes

Answer:

x>4

d'ou: x-4>4-4

x-4>0 voilà bonnne journée

Step-by-step explanation:

Answer:

665

Step-by-step explanation:

PLEASE MARK ME AS BRAINLIEST AND HAVE A NICE DAY :)

Answer:

665

Step-by-step explanation:

350 - 30( - 14 + 3.5) ← evaluate the parenthesis

= 350 - 30( - 10.5) ← distribute parenthesis by - 30

= 350 + 315

= 665

The answer is A. Springsville has several different activities.

Answer:

2.5

Step-by-step explanation:

Let M and P stand for the money that Mike(M) and Pete(P) have.

We discover that M + P = $84.00

We also find that M = $24.00

This means that :

M + P = $84.00

$24.00 + P = $84.00

P = $60.00

The ratio of P to M is ($60.00/$24.00) or 2.5   (P/M - 2.5)

Answer:

$26.42

Step-by-step explanation:

P = 30 * 0.82 * 1.074 = 26.42

Answer:

[tex]\left( x-3\right)^{2} +\left( y-\frac{3}{2} \right)^{2} =\frac{13}{4}[/tex]

Step-by-step explanation:

Let  A(2,3) and B(4,0) be the end points of the diameter

then the segment AB is the diameter of the circle

Then the center of the circle (point M) is the midpoint of segment AB

Then M( (2+4)/2 , (3+0)/2 ) then M( 3 , 3/2 )

Now let’s find the radius r of our circle :

r = AB/2

Then

[tex]r=\frac{AB}{2} =\frac{\sqrt{(0-3)^{2}+(4-2)^2} }{2} =\frac{\sqrt{13} }{2}[/tex]

Then Equation of the circle is:

[tex]\left( x-3\right)^{2} +\left( y-\frac{3}{2} \right)^{2} = \left( \frac{\sqrt{13} }{2} \right)^{2} \\\Longrightarrow \left( x-3\right)^{2} +\left( y-\frac{3}{2} \right)^{2} =\frac{13}{4}[/tex]

The exact numbers listed in this problem are given by:

Exact numbers are numbers that are not rounded. Volumes and lengths, for example, are usually rounded, hence they cannot be called exact.

Thus, the exact numbers listed in this problem are given by:

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[tex]\qquad\qquad\huge\underline{{\sf Answer}}♨[/tex]

Let's solve ~

The given equations are :

[tex]\qquad \sf  \dashrightarrow \:x + y = 32[/tex]

and

[tex]\qquad \sf  \dashrightarrow \:y = 7x[/tex]

Now, plug in the value of y from equation 2 into equation 1 to find out the value of x ~

[tex]\qquad \sf  \dashrightarrow \:x + y = 32[/tex]

[tex]\qquad \sf  \dashrightarrow \:x + 7x = 32[/tex]

[tex]\qquad \sf  \dashrightarrow \:8x = 32[/tex]

[tex]\qquad \sf  \dashrightarrow \:x = 32 \div 8[/tex]

[tex]\qquad \sf  \dashrightarrow \:x = 4[/tex]

Now, plug the value of x in equation 2 to find y

[tex]\qquad \sf  \dashrightarrow \:y = 7x[/tex]

[tex]\qquad \sf  \dashrightarrow \:y = 7 \times 4[/tex]

[tex]\qquad \sf  \dashrightarrow \:y = 28[/tex]

➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖➖

Answer:

-1

Step-by-step explanation:

angle 0: 7pie/4

=7*180/4

=1260/4

=315

hence reference angle(0)= 315

now, tan 0 = tan315

= tan(360-45)

= -tan45

= -1

Answer: Division Property of equality

Step-by-step explanation:

5d= 75

1. Isolate the variable and remember, if the number is next to the letter, it means to multiply.

2. Reverse PEMDAS so instead of multiplying, divide instead.

3. 75/ 5 equals 15.

d=15

Answer: d=. 15

Step-by-step explanation:

Answer:

14

Step-by-step explanation:

2x((5-3)+(7-2)) = 14

Answer:

Step-by-step explanation:

Hailey paid 80% of the regular price.

We have Hailey who paid 40$ for a jacket whose regular price was 50$.

Assume that she paid [x]% of the regular price.

Then, we can write -

40 = x% of 50

40 = (x/100) x 50

x = (4000/50)

x = 80%

Therefore, Hailey paid 80% of the regular price.

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