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3 years ago

1/4(1/3k+9)=6 step 1- 1/3k=15 step 2- 1/3k=15 step 3- k=5 find Olgas mistake step 1 step 2 steps 3 Olga did not make a mistake

Mathematics

1 answer:

shtirl [24]3 years ago

3 0

Answer:

Step 3 contains error.

Step-by-step explanation:

The given equation is :

$\dfrac{1}{4}(\dfrac{1}{3}k+9)=6$

Step 1.

Cross multiplying,

$(\dfrac{1}{3}k+9)=24$

Step 2.

Subtract 9 from both sides

$\dfrac{1}{3}k+9-9=24-9\\\\\dfrac{1}{3}k=15$

Step 3.

Cross multiplying

$k=15\times 3\\\\k=45$

So, there is an error in step 3. The correct answer should be 45.

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Cot^2 135-sin210+5cos^2 225

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4 years ago

What is the common ratio for this geometric sequence?<br> 16, 8, 4, 2, …..

vovikov84 [41]

Answer:

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Step-by-step explanation:

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3 years ago

Read 2 more answers

1-2+3-4+5-6+..+99-100.

aliya0001 [1]

-50

So you want to pair them up
(1-2)+(3-4)+(5-6)..+(99-100)
And write the answer for each pair
(-1)+(-1)+(-1)..+(-1)
When looking at this you can see that each pair equals -1
So you divide 100 by 2 and multiply that by the -1
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You would use the same method if you were going up to a number like a 500
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4 years ago

A parallelogram has an area of x2 + 9x - 36.

malfutka [58]

Answer:

Step-by-step explanation:

Please use " ^ " to indicate exponentiation:

A = x^2 + 9x - 36. This factors into A = (x + 12)(x - 3). We can assume that the length of the parallelogram is x + 12 and that the width is x - 3.

Note that if x = 3 the area becomes zero. So: x must be greater than 3, so that the (x - 3) factor is positive.

Example: If x = 4, then the dimensions of the parallelogram are 4 + 12, or 16, and 4 - 3, or 1.

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3 years ago

What is the conditional frequency of a student who rides the bus being late to class first period?

Novosadov [1.4K]

Answer:

1/5

Step-by-step explanation:

The Constraint is ; those who rode the bus, hence it is conditional because we aren't focused on students, only students who rode the bus.

Now we want the frequency of those who were late Given that they rode the bus : for these we have 3 students

Total number of students who rode the bus , total possible outcome = 15

Hence, the conditional frequency = (number who rode bus and were late / otal number who rode the bus)

Hence, we have ; 3 / 15 = 1 / 5

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3 years ago