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denis-greek [22]

2 years ago

11

A researcher randomly selects 3 fish from among 8 fish in a tank and puts each of the 3 selected fish into different containers.

how many ways can this be done?

1 answer:

Elina [12.6K]2 years ago

6 0

First he can select one fish among 8, after that one among 7 of them and finally one among 6 fish.
8 * 7 * 6 = 336
Then he puts each of selected fish into different containers:
336 * 3 * 2 * 1 = 2,016
Answer: This can be done in 2,016 ways.

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hodyreva [135]

Answer:

Each birthday card costs $2.2 ⇒ answer c

Step-by-step explanation:

* Lets explain how to solve the problem

- Package A contains 3 birthday cards and 2 thank-you notes

- It costs $9.60

- Package B contains 8 birthday cards and 6 thank-you notes

- It costs $26.60

- x represents the cost of birthday card and y represents the cost of

thank-you note

* Lets change these information to two equations

∵ x represents the cost of each birthday cards

∵ y represents the cost of each thank-you notes

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∵ Bag A costs $9.60

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∵ Bag B contains 8 birthday cards and 6 thank-you notes

∵ Bag B costs $26.60

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∴ -x = -2.2

- Multiply both sides by -1

∴ x = 2.2

∵ x represents the cost of each birthday cards

∴ The cost of each birthday card is $2.2

* Each birthday card costs $2.2

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