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4 years ago

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4. A circuit board uses three switches. We have three switches of type I, five of type II, and seven of type III. How many diffe

rent choices are there?

1 answer:

siniylev [52]4 years ago

4 0

Answer:

105

Step-by-step explanation:

On the assumption that each switch must be a different type, we need to choose 1 type I switch from 2, 1 type II switch from 5 and 1 type III switch from 7.

The number of ways of picking $r$ objects from $n$ objects is $\binom{n}{r}=\dfrac{n!}{r!(n-r)!}$

$\binom{3}{1}=\dfrac{3!}{1!2!}=3$

$\binom{5}{1}=\dfrac{5!}{1!4!}=5$

$\binom{7}{1}= \dfrac{7!}{1!6!}=7$

The total number of different choices = $3\times5\times7=105$

If there's no restriction on the choices, we would need to pick 3 socks from a total of 15.

$\binom{15}{3}=\dfrac{15!}{3!12!}=105$

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Expand ( 8 x − 3 ) ( 8 x − 3 ) using the FOIL Method.

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3 years ago

On the go company has two monthly plans for its customers. The EZ pay plan cost a $0.15. Solve the equation, showing each step.

sveticcg [70]

The equation shows that the number of minutes when the plans will be equal will be 400 minutes.

<h3>How to calculate the value?</h3>

From the information, we are told that the on the go company has two monthly plans for its customers. The EZ pay plan cost a $0.15. The 40 to go plan costs $40 per month plus $0.05 per minute.

The cost for the first plan will be:

= 0.15 ×x

= 0.15x

The cost for the second plan will be:

= 40 + 0.05x

The number of minutes when the plans will be equal will be:

0.15x = 40 + 0.05x

0.15x - 0.05x = 40

0.10x = 40

x = 400

Therefore, the equation shows that the number of minutes when the plans will be equal will be 400 minutes.

Complete question:

On the go company has two monthly plans for its customers. The EZ pay plan cost a $0.15. The 40 to go plan costs $40 per month plus $0.05 per minute. Solve the equation.

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brainly.com/question/2972832

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2 years ago

One to one relationships describe situations where people are matched with with unique identities, such as their Emirates ID num

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3 years ago

Suppose that the functions u and w are defined as follows.

jasenka [17]

Answer(there are assumptions for this answer that you need to confirm and look at):

Assumptions: $u(x)=x^2+3$ and $w(x)=\sqrt{x+2}$

Answer if the operation is multiplication:

If you meant a closed dot which is the symbol for multiplication.

$(u \cdot w)(2)=14$

$(w \cdot u)(2)=14$

Answer if the operation is composition:

If you meant an open dot which is the symbol for composition.

$(u \circ w)(2)=7$

$(w \circ u)(2)=3$

Note: I don't know if you actually meant $w(x)=\sqrt{x+2}$ or if $w(x)=\sqrt{x}+2$ . Please let me know one way or the other.

Step-by-step explanation:

If we assume the functions are:

$u(x)=x^2+3$

$w(x)=\sqrt{x+2}$

$u \cdot w=w \cdot u$ since multiplication is commutative.

$u(2)=2^2+3$

$u(2)=4+3$

$u(2)=7$

$w(2)=\sqrt{2+2}$

$w(2)=\sqrt{4}$

$w(2)=2$

We are asked to find $(u \cdot w)(2)$ and $(w \cdot u)(2)$ .

The order doesn't matter in multiplication.

$(u \cdot w)(2)$

$u(2) \cdot w(2)$

$7 \cdot 2$

$14$

$(w \cdot u)(2)$

$w(2) \cdot u(2)$

$2 \cdot 7$

$14$

Now you might have meant composition which symbolized with an open circle, not a closed one.

$(u \circ w)(2)$

$u(w(2))$

$u(2)$ since $w(2)=2$

$2^2+3$

$4+3$

$7$

$(w \circ u)(2)$

$w(u(2))$

$w(7)$ since $u(2)=7$

$\sqrt{7+2}$

$\sqrt{9}$

$3$

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4 years ago

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Kruka [31]

Answer:

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Step-by-step explanation:

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3 years ago

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