A. 12x+y=6<span>B. −2x+y=6</span>
Answer:
a) 0.2
b) 0.2
c) 0.5
Step-by-step explanation:
Let
be the event "the car stops at the signal.
In the attached figure you can see a tree describing all possible scenarios.
For the first question the red path describes stopping at the first light but not stopping at the second. We can determine the probability of this path happening by multiplying the probabilities on the branches of the tree, thus

For the second one the blue path describes the situation

For the las situation the sum of the two green path will give us the answer

Sometimes; though your question isn't that clear.
To find the number of red bricks used, you can create a part to part to whole ratio from the simple ratio of red to grey brick they give.
Then, use the total to create an equivalent ratio with the actual total number of bricks (140).
<u>5 red </u> <u>100 red</u>
<u>2 grey</u> = <u>40 grey</u>
7 total 140 total
<u>
</u>Each time, the simple ratio was multiplied by 20 to get the actual totals for each color.
<u>
</u>There were 100 red bricks used.<u>
</u>
3x-4=-19
you add -4 to both sides and get 3x=15 then divide 3 by both sides and get x=5 (15 divided by 3 is 5)