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3 years ago

Is 81 divisible by 3?

2 answers:

4 0

Add up the digits that make 81 as follows: 8 + 1 = 9

We know that if the sum of the numbers that make up 81 is divisible by 3, then 81 is divisible by 3.

<span>Since the sum of the digits in 81 is divisible by 3, 81 is also divisible by 3. Thus, the answer to the question "Is 81 divisible by 3?" is as follows: </span>

<span>Yes</span>

AlexFokin [52]3 years ago

3 0

Yes 81 is divisible by 3
the answer is 27
because 81 divided by 3 = 27

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Novosadov [1.4K]

Answer:

There is no solution, y-int of one line is positive

Step-by-step explanation:

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3 years ago

6. A tank contains 100-gallon of pure water. At time t = 0, a solution containing 2 lb of salt per gallon flows into the tank at

SOVA2 [1]

Answer:

The answer is below

Step-by-step explanation:

Let Q represent the amount of salt in the tank at time t.

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3 years ago

The ratio of marbles to stones is 5 to 7 if there are 35 marbles how many stones is there?

icang [17]

5 : 7
Marbles : Stones

35/5 = 7
So stones
= 7 * 7
49

=35 : 49

3 0

3 years ago

Read 2 more answers

PLEASE HURRY 50 POINTS Answer Both parts and I will reward Brainliest

vlabodo [156]

We have:

$a_1=-3$

and:

$r=4$

so:

$$\sum\limits_{n=2}^5\,-3\cdot4^{n-1}=\sum\limits_{n=1}^5\,-3\cdot4^{n-1}-a_1=S_5-a_1=\frac{-3-(-3)\cdot 4^5}{1-4}-(-3)=$

$=\dfrac{-3-(-3)\cdot 1024}{-3}+3=\dfrac{-3(1-1024)}{-3}+3=1-1024+3=\boxed{-1020}$

It is a finite sum, so it is convergent.

6 0

3 years ago

Select all that apply.

vfiekz [6]

Answer:

1/3 , 4/15 , 5/6

Step-by-step explanation:

All you have to do is plug the fractions in your calculator and you see that 1/3, 4/15, and 5/6 are repeating, but the others stop after only a couple of decimal places.

Hope this helps!

4 0

3 years ago