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zhannawk [14.2K]

3 years ago

8

According to the scores on the last math test, 80%, or 20. of the students in the class received an A Find the number of student

s in the entire class.

1 answer:

Kitty [74]3 years ago

4 0

Answer:

25 students

Step-by-step explanation:

.8x = 20

x = 25 students

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A panther cub weighs 890 grams. At birth the cub weighed 450 grams. What is the percent increase in the panther cub's weight rou

Ksju [112]

Answer: 98%

Step-by-step explanation:

First subtract the birth weight from the new weight (890-450=440). To find what percent of 450 that is, divide the difference by 450 (440/450=97.78). Round to the nearest whole number (97.78==>98).

6 0

3 years ago

Matt buys a new fish tank. The fish tank is in the shape of a cuboid. The diagram shows water in the tank. 30 cm 30 cm 100 cm Ma

lyudmila [28]

Answer: Yes, but only if he houses 37, 38, 39, or 40 fish

Anything larger than 40 and he'll need more room.

==========================================================

Explanation:

The tank is 30 cm by 30 cm by 100 cm. The volume is 30*30*100 = 90,000 cm^3 which is shorthand for "cubic centimeters".

We're told that 1000 cm^3 = 1 liter, which means the 90,000 cm^3 converts to (90,000)/(1000) = 90 liters.

The fish tank is 90 liters.

Since 1 gallon = 4.5 liters, this means the 90 liter tank converts to 90/(4.5) = 20 gallons

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

Your teacher mentions "He can keep 2 small fish for every 1 gallon".

Since the tank is 20 gallons, that means he can keep 20*2 = 40 fish. This value is larger than 36, so Matt is correct to a point. If Matt is thinking 37, 38, 39, or 40 fish then he would be correct. If Matt is wanting more than 40 fish, then he'll need a bigger tank.

In short, he can't have any number over 36 and can only have 4 specific values (the four values mentioned earlier).

So technically, Matt is correct, but strong clarification is needed.

4 0

3 years ago

A turkey costs $1.05 per pound. There are going to be fifteen people at Thanksgiving dinner. Plan for each person to eat two, 3/

valina [46]

Answer:

<em>I will need to buy 22.5 pounds of turkey and pay $23.63</em>

Step-by-step explanation:

<u>Proportions</u>

Each person is planned to eat 2 x 3/8 pound servings of turkey for thanksgiving dinner. This means each person will eat

$2\cdot\frac{3}{4}=\frac{3}{2}$

pounds of turkey.

There are going to be 15 people at the dinner, thus the total turkey needed is:

$15\cdot\frac{3}{2}=22.5~pounds$

The turkey costs $1.05 per pound, thus the total cost is

22.5*$1.05 = $23.63

I will need to buy 22.5 pounds of turkey and pay $23.63

6 0

3 years ago

Three vertices of a parallelogram are shown in the figure below. Give the coordinates of the fourth vertex.

topjm [15]

Given:

The three vertices of a parallelogram are (-3,8), (4,5), (2,-5).

To find:

The fourth vertex of the parallelogram.

Solution:

Let the vertices of the parallelogram are A(-3,8), B(4,5), C(2,-5) and D(a,b).

We know that, diagonals of a parallelogram bisect each other. It means midpoints of both diagonals are same.

Midpoint formula:

$Midpoint=\left(\dfrac{x_1+x_2}{2},\dfrac{y_1+y_2}{2}\right)$

Two diagonals of ABCD are AC and BD.

Midpoint of AC = Midpoint of BD

$\left(\dfrac{-3+2}{2},\dfrac{8-5}{2}\right)=\left(\dfrac{4+a}{2},\dfrac{5+b}{2}\right)$

$\left(\dfrac{-1}{2},\dfrac{3}{2}\right)=\left(\dfrac{4+a}{2},\dfrac{5+b}{2}\right)$

On comparing both sides, we get

$\dfrac{4+a}{2}=\dfrac{-1}{2}$

$4+a=-1$

$a=-1-4$

$a=-5$

And,

$\dfrac{5+b}{2}=\dfrac{3}{2}$

$5+b=3$

$b=3-5$

$b=-2$

Therefore, the coordinates of fourth vertex are (-5,-2).

3 0

2 years ago

A mathematical formula designed to predict population fluctuations in a community could be called a(an)

kvasek [131]

It would be called an ecological model.

5 0

3 years ago