Rules for SN = must be a number from 1 and less than 10 times a power of 10

So our number becomes

2.22 x 10⁸ - It takes a move of 8 places to the right to make the number 222,000,000

6 0

3 years ago

a jar contains 5 blue marbles and 3 red marbles. suppose you choose a marble at random and do not replace it. then choose a seco

lina2011 [118]

$\mathbb P(R_1\cap R_2)=\mathbb P(R_2\mid R_1)\mathbb P(R_1)$

The probability of drawing a red marble on the first attempt is

$\mathbb P(R_1)=\dfrac{\dbinom31}{\dbinom51}=\dfrac35$

After the first marble is drawn, and we know it to be red, we're drawing the next marble from a pool with one less marble than before (i.e. conditioning on the event $R_1$ ). So

$\mathbb P(R_2\mid R_1)=\dfrac{\dbinom21}{\dbinom71}=\dfrac27$

And so

$\mathbb P(R_1\cap R_2)=\dfrac35\cdot\dfrac27=\dfrac6{35}$

4 0

3 years ago