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Louisiana biologists tagged 250 fish in the oxbow lake False River on October 5. On a later date, they found 7 tagged fish in a sample of 350 fish. Estimate the total number of fish in False River to the nearest hundred.

At a school, the school population is 2/5 boys. There are 450 boys in the school. How many total students are in the school?

A bag contains quarter and dimes in a ratio of 3:5. If there is $6 in quarters in the bag, how many dimes are there?

Respuesta :

1. Set up a ratio:

7 tagged / 350 fish = 250 tagged / x fish

Solve for x:

x = (350 * 250) / 7

x = 12,500 fish

2. Divide number of boys by the population ratio:

450 / 2/5 =  (450 *5) /2 = 2250 / 2 = 1125 total students.

3.  4 quarters = $1, so they have 24 quarters total.

The ratio 3:5 means for every 3 quarters there are 5 dimes.

24 quarters / 3 = 8

8 x 5 = 40 dimes.

(1)  The population of fish in the False river is 12500.

(2) There are 1125  total number of students in the school .

(3) There are 40 dimes in the bag.

(1) Number of fish tagged by Louisiana biologists =  250

On the next day a sample was collected from the False river

The number of fish in the sample = 350

Number of tagged fish in the sample =  7

Let the population of fish in the False river  = P

Takin the ratio we can

[tex]\rm \dfrac{7}{350}= \dfrac{250}{P} \\\\P = (250)(350)/(7)\\P = 12500[/tex]

So the population of fish in the False river = 12500

(2) The number of boys in the school = 450

Let the total number of students in the  school be B

According to the given condition

[tex]\rm \dfrac{2}{5}\times B = 450\\\\B = (450\times 5) /2 \\B = 2250/2 =1125[/tex]

So the total number of students in the school = 1125

(3) Let the number of dimes in the bag be x

According to the given condition we can write

[tex]\rm \dfrac{Number\; of\; quarters }{Number\; of\; dimes } = \dfrac{3}{5} ........(1)[/tex]

Also  it is given that there are $6 in quarters in the bag.

$1 = 4 quarters

So $6 has  [tex]\rm 4\times 6 = 24 \; quarters[/tex]

So we can put this value in equation (1)

[tex]\dfrac{24}{x} =\dfrac{3}{5} \\\\x = 40 dimes[/tex]

So we can conclude that there are 40 dimes in the bag.

For more information please refer to the link  given below

https://brainly.com/question/21379025