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3 years ago

Natalie can do 26 push ups in 2 minutes how many can she do in 7 minutes? set up porportion

Mathematics

1 answer:

Mumz [18]3 years ago

8 0

Answer:

In seven minutes she can do 91 push ups

Step-by-step explanation:

26*3=78

78+13=91

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Help me its due in a little bit

Andrews [41]

Answer:

false

Step-by-step explanation:

6 0

2 years ago

aleksklad [387]

Answer:

..2.50x + 3.75x = 15..

Step-by-step explanation:

i think

8 0

2 years ago

A rectangular box with a square base is to be constructed from material that costs $9 per ft2 for the bottom, $5 per ft2 for the

kramer

Answer:

$18.73ft^3$

Step-by-step explanation:

Let

Side of square base=x

Height of rectangular box=y

Area of square base=Area of top= $(side)^2=x^2$

Area of one side face= $l\times b=xy$

Cost of bottom=$9 per square ft

Cost of top=$5 square ft

Cost of sides=$4 per square ft

Total cost=$204

Volume of rectangular box= $V=lbh=x^2y$

Total cost= $9(x^2)+5x^2+4(4xy)=14x^2+16xy$

$204=14x^2+16xy$

$204-14x^2=16xy$

$y=\frac{204-14x^2}{16x}=\frac{102-7x^2}{8x}$

Substitute the values of y

$V(x)=x^2\times \frac{102-7x^2}{8x}=\frac{1}{8}(102x-7x^3)$

Differentiate w.r.t x

$V'(x)=\frac{1}{8}(102-21x^2)=0$

$V'(x)=0$

$\frac{1}{8}(102-21x^2)=0$

$102-21x^2=0$

$102=21x^2$

$x^2=\frac{102}{21}=4.85$

$x=\sqrt{4.85}=2.2$

It takes positive because side length cannot be negative.

Again differentiate w.r. t x

$V''(x)=\frac{1}{8}(-42x)$

Substitute the value

$V''(2.2)=-\frac{42}{8}(2.2)=-11.55$

Hence, the volume of box is maximum at x=2.2 ft

Substitute the value of x

$y=\frac{102-7(2.2)^2}{8(2.2)}=3.87 ft$

Greatest volume of box= $x^2y=(2.2)^2\times 3.87=18.73 ft^3$

5 0

3 years ago

What is the following qoutient? 3√8/4√6

kogti [31]

Answer:

3 sqrt(3)

----------- or -----------

2 sqrt(3) 2

Step-by-step explanation:

3 sqrt(8)

-----------------

4 sqrt(6)

3 sqrt(4*2)

-----------------

4 sqrt(3*2)

We know that sqrt(ab) = sqrt(a) sqrt(b)

3 sqrt(4) sqrt(2)

------------------------

4 sqrt(3) sqrt(2)

Canceling the sqrt(2) and sqrt(4) is 2

3*2

----------

4 sqrt(3)

-----------

2 sqrt(3)

We can simplify the answer be multiplying by sqrt(3)/sqrt(3)

3 sqrt(3)

----------- * ----------

2 sqrt(3) sqrt(3)

3 sqrt(3)

-----------

2 *3

sqrt(3)

-----------

3 0

2 years ago

Which of the following is equal to the expression listed below?

olya-2409 [2.1K]

Answer:

27 + 36 = 63

A. (9 + 3)(9 + 4) = 12 × 13 = 156

B. 9(3 + 4) = 9 × 7 = 63

C. 9 + (3 × 4) = 9 + 12 = 21

D. (9 × 3)(9 × 4) = 27 + 36 = 63

Option B and D

8 0

3 years ago