Given:
The ratio of red and blue cubes is 4:7.
After adding 10 more red cubes the ratio of red and blue cubes is 6:7.
To find:
The number of blue cubes.
Solution:
The ratio of red and blue cubes is 4:7.
Let the number of red and blue cubes be 4x and 7x respectively.
After adding 10 more red cubes.
Number of red cubes = 4x+10
Then, the ratio of red and blue cubes is 6:7.
Divide both sides by 14.
Now,
Number of blue cubes in the bag is
Therefore, the number of blue cubes is 35.
<h3>Answer: 1/6</h3>
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Explanation:
There are two methods to approach this type of problem.
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Method 1
A = junior
B = girl
P(A) = probability of selecting a junior
P(B) = probability of selecting a girl
P(B) = (number of girls)/(number total)
P(B) = (4+7+3+4)/(4+4+5+7+2+3+1+4)
P(B) = 18/30
P(B) = 9/15
P(A and B) = probability of selecting a girl who is a junior
P(A and B) = (number of girl juniors)/(number total)
P(A and B) = 3/30
P(A and B) = 1/10
P(A given B) = P(A and B)/P(B)
P(A given B) = (1/10) divided by (9/15)
P(A given B) = (1/10) times (15/9)
P(A given B) = (1*15)/(10*9)
P(A given B) = 15/90
P(A given B) = 1/6
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Method 2
This method doesn't involve dividing two fractions which could get messy, which is why I find this the easier route. Since we are given the person is a girl, this means we only need to focus on the "girls" column. There are 3 who are juniors out of 4+7+3+4 = 18 total. The probability of selecting a girl junior is 3/18 = 1/6
Substract 2/3 from each side.
X= 2/3, assuming that you are solving for X.
Answer: I think b
Step-by-step explanation: If i get it wrong im terribly sorry plz forgive if it's wrong
