Hi i am Grace and i realllyyyyyy need help on this. If you could please help that would be great.

Mathematics

1 answer:

uranmaximum [27]3 years ago

7 0

The probability of picking a black ball first is $\dfrac{4}{5}$ , because there are 4 black balls and 1 white ball which is 5 balls in total. After picking the first ball, 4 balls remain - 3 black and 1 white, so the probability of picking a white ball is $\dfrac{1}{4}$ .
So, the probability of picking a black ball first followed by a white ball is $\dfrac{4}{5}\cdot\dfrac{1}{4}=\dfrac{1}{5}$

You might be interested in

Pls anyone help need help

Neko [114]

Answer:

- 2 ≤ n < 8

Step-by-step explanation:

The closed circle at - 2 indicates that n can equal - 2

The open circle at 8 indicates that n cannot equal 8

Otherwise n can be all value between - 2 and 8 including - 2, thus

- 2 ≤ n < 8

3 0

3 years ago

Evaluate the expression.<br> 621+5) - 3

Gennadij [26K]

Answer:

I think its 623

8 0

4 years ago

Find the x- and y- intercepts of parabola y=5x^2-16x+10

____ [38]

Y-INTERCEPT

$y = 5x^2 - 16x + 10$

The y-intercept is where the equation/curve/parabola cosses the y-axis.

The y-axis is where x = 0. (The x-axis is where y = 0)

To find the y-intercept:

$\text{y-axis} \rightarrow \text{x = 0} \rightarrow y = 5(0)^2 -16(0) + 10 = 10$

The y-intercept must be at (0, 10)

X-INTERCEPT (ROOTS/SOLUTIONS)

$y = 5x^2 - 16x + 10\\\text{make it equal 0}\\y = 0\\\therefore 5x^2 - 16x + 10 = 0$

We need to use the quadratic formula

The quadratic formula helps us find what values of $x$ make the equation = 0

Quadratic formula: $x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

$x=\frac{-(-16) + \sqrt{(-16)^2-4(5)(10)}}{2(5)}\\\\x = \frac{16 + \sqrt{256-200}}{10}\\x = \frac{16 + \sqrt{56}}{10}\\x = \frac{16 + 2\sqrt{14}}{10}\\x = \frac{8 + \sqrt{14}}{5}\\\\\\x=\frac{-(-16) - \sqrt{(-16)^2-4(5)(10)}}{2(5)}\\\text{doing the same thing...}\\\text{end up with...}\\x = \frac{8 - \sqrt{14}}{5}\\$