PLZ HELP ME WITH THISSSS

First is all possibilities. Let's do it one step at a time. The first step is the number, what are all the numbers that can be chosen? 1 2 and 3. then, when you pick1, what are all the letters that can be chosen? A B and C. Do this for 2 and 3 and you get all possibilities.

{1A, 1B, 1C, 2A, 2B, 2C, 3A, 3B, 3C}

When you have steps like this you can multiply the number of results to get the total number of possibilities as well. Step one has 3 results, step 2 has 3 results, that means there are 3*3 total, which is 9. Do be careful it matches this kind of setup, where the step 2 is the same for all step 1s. So if instead if you got 1 for step 1 you picked from a bag with 3 things, then for 2 you picked from a different bag with a different number, that multiplication trick wouldn't work.

Now just pick throught he sample space to find all with C. There are three, {1C, 2C, 3C}

7 0

4 years ago

Two trains are 400 miles apart, and their speeds differ by 10 mph. They travel toward each other and meet in 4 hours. Find the s

Katen [24]

So.. the two trains, are 400 miles apart, their speeds differ by 10, so one train is faster than the other.. .let's say train A is faster than train B, by 10mph

so if train A has a speed rate of "r", then B has a rate of "r - 10"

after train A has beeng running for 4hrs, it has travelled a distance "d"

train B has travelled also for 4hrs, they're both 400 miles apart, and travelling towards each other, so the total distance travelled by both is 400miles

so after 4hours B has travelled the slack from 400 and "d", namely 400 - d

recall your d = rt --> distance = rate * time

$\bf \begin{array}{lccclll}
&distance&rate&time\\
&-----&-----&-----\\
\textit{Train A}&d&r&4\\
\textit{Train B}&400-d&r-10&4
\end{array}\\\\
-----------------------------\\\\

\begin{cases}
\boxed{d}=4r\\
400-d=(r-10)4\\
----------\\
400-\boxed{4r}=(r-10)4
\end{cases}$

solve for "r", to find the speed of the faster train A

what's the speed of B? well, B's rate is r - 10

4 0

3 years ago

Im working on a math sheet

SSSSS [86.1K]

Answer:

b

Step-by-step explanation:

can i have brainlyest

:D

4 0

2 years ago