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2 years ago

Please please please help me find the answerrrrr

Mathematics

1 answer:

ehidna [41]2 years ago

7 0

Answer:

320.28?

Step-by-step explanation:

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Ricardo bought a bicycle for $98.00. He sold it to his friend Sandy for 5/6

svet-max [94.6K]

Answer:

Ricardo bought it for $98.00

Sandy bought it for $81.66 [5/6×98]

Jennifer bought it for $48.99. [ 3/5×81.66]

3 0

3 years ago

Let A be a set of numbers.

LUCKY_DIMON [66]

Answer:

a. closed under addition and multiplication

b. not closed under addition but closed under multiplication.

c. not closed under addition and multiplication

d. closed under addition and multiplication

e. not closed under addition but closed under multiplication

Step-by-step explanation:

Let A be a set of all integers divisible by 5.

Let $x,y$ ∈A such that $x=5m\,,\,y=5n$

Find $x+y,xy$

$x+y=5m+5n=5(m+n)$

So, $x+y$ is divisible by 5.

$xy=(5m)(5n)=25mn=5(5mn)$

So,

$xy$ is divisible by 5.

Therefore, A is closed under addition and multiplication.

Let A = { 2n +1 | n ∈ Z}

Let $x,y$ ∈A such that $x=2m+1\,,\,y=2n+1$ where m, n ∈ Z.

Find $x+y,xy$

$x+y=2m+1+2n+1=2m+2n+2=2(m+n+1)$

So,

$x+y$ ∉ A

$xy=(2m+1)(2n+1)=4mn+2m+2n+1=2(2mn+m+n)+1$

So,

$xy$ ∈ A

Therefore, A is not closed under addition but A is closed under multiplication.

$Let A=\{2,5,8,11,14,...\}$

Let $x=2,y=5$ but $x+y=2+5=7$ ∉A

Also,

$xy=2(5)=10$ ∉A

Therefore, A is not closed under addition and multiplication.

Let A = { 17n: n∈Z}

Let $x,y$ ∈ A such that $x=17n,y=17m$

Find x + y and xy

$x+y=17n+17m=17(n+m)$

$xy=(17m)(17n)=289mn=17(17mn)$

So,

$x+y,xy$ ∈ A

Therefore, A is closed under addition and multiplication.

Let A be the set of nonzero real numbers.

Let $x,y$ ∈ A such that $x=-1,y=1$

Find x + y

$x+y=-1+1=0$

So,

$x+y$ ∈ A

Also, if x and y are two nonzero real numbers then xy is also a non-zero real number.

Therefore, A is not closed under addition but A is closed under multiplication.

4 0

2 years ago

2 of 6

Elodia [21]

Answer:

89:120

Step-by-step explanation:

convert the both times to minutes

2 hours is 120 mins

89:120

both divisible by 1

89:120

it cant be simplified further

8 0

2 years ago

Element X is a radioactive isotope such that every 90 years, its mass decreases by half. Given that the initial mass of a sample

steposvetlana [31]

Answer:

approximately 27 grams

Work Shown:

Half life formula

y = A*(0.5)^(x/H)

where,

A = starting amount = 30 grams

H = half life period = 90 years

x = number of years that pass by = 12

y = amount left over after x years

Let's plug the values for x, A and H into the formula to find y

y = A*(0.5)^(x/H)

y = 30*(0.5)^(12/90)

y = 27.3516746567466

y = 27 .... rounding to the nearest whole number

4 0

2 years ago

Please help me I will give a brainly

bearhunter [10]

I believe the answer is “one solution”. I hope this helps :)

8 0

1 year ago