In a group of 9 children, there are twice as many girls as boys, and twice as many right-handed people as there are left

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In a group of 9 children, there are twice as many girls as boys, and twice as many right-handed people as there are left-handed people. If a third of the boys are left-handed, how many girls are right-handed?

A. 1
B. 3
C. 4
D. 5
E. 6


OA C

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BTGmoderatorDC wrote:
Wed Jun 30, 2021 2:58 pm
In a group of 9 children, there are twice as many girls as boys, and twice as many right-handed people as there are left-handed people. If a third of the boys are left-handed, how many girls are right-handed?

A. 1
B. 3
C. 4
D. 5
E. 6


OA C

Source: Manhattan Prep
As per the question !!
The total number of boys \(= 3,\) total number of girls \(=6\)
Right-handed \(= 6,\) Left-handed \(= 3\)
\(\dfrac{1}{3}\)(Boys)\(=\)Left handed \(= 1\)

Number of left-handed people left \(= 2 =\) girls

Therefore, the total number of right-handed girls \(= 6- 2 =4\)

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BTGmoderatorDC wrote:
Wed Jun 30, 2021 2:58 pm
In a group of 9 children, there are twice as many girls as boys, and twice as many right-handed people as there are left-handed people. If a third of the boys are left-handed, how many girls are right-handed?

A. 1
B. 3
C. 4
D. 5
E. 6


OA C

Source: Manhattan Prep
In a group of 9 children, there are twice as many girls as boys
Let x = the number of boys
So, 2x = the number of girls
We can write: x + 2x = 9
Solve to get x = 3, which means there are 3 boys and 6 girls

In a group of 9 children, there are twice as many right-handed people as there are left-handed people.
Using the same approach we can see that there are 3 left-handed people, and 6 right-handed people.

If a third of the boys are left-handed, how many girls are right-handed?
There are 3 boys.
1/3 of 3 = 1.
So there 1 left-handed boy, which means the other 2 boys are right-handed

There are 6 right-handed people all together.
If 2 of them are boys, then the other 4 must be girls

Answer: C
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