Does anyone know the answer?

Mathematics

2 answers:

Helen [10]3 years ago

5 0

The answer would be 60, if you add 13,15, and 12 up you get 40. Those numbers would be considered 2/3 of all the marbles. Divide 40 by 2 to get how many marbles is 1/3. You would get 20 being a third if the marbles. Add that to the original 40 and you’ll get a total of 60.

ddd [48]3 years ago

5 0

Answer: 60

Step-by-step explanation:

Let R be number of red marbels

Let T be Total number of marbels in bag

Now,

T = 13 + 15 + 12 + R

T = 40 + R

Now,

Let P(R) be probability of getting red marble.

P(R) = R / T

1/3 = R / ( 40 + R )

40 + R = 3R

2R = 40

R = 20

So,

T = 40 + R

T = 40 + 20

T = 60

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A rectangular box has a square base with an edge length of x cm and a height of h cm. The volume of the box is given by V = x2h

creativ13 [48]

It is given in the question that

A rectangular box has a square base with an edge length of x cm and a height of h cm. The volume of the box is given by

$V = x^2h cm^3$

And the edge length of the base is 12 cm, the edge length of the base is decreasing at a rate of 2 cm/min, the height of the box is 6 cm, and the height is increasing at a rate of 1 cm/min.

Here we differentiate V with respect to t, and we use product rule, that is

$V = 2xh(dx/dt)+ x^2(dh/dt)$