Question

The grid above shows the number of hours worked last week by $12$ students of various ages at after-school jobs. Which of the following is true, according to this grid?

• A. Half of the students worked more than $12$ hours each
• B. One student worked exactly $15$ hours
• C. One $16$ year old worked more than $11$ hours
• D. More $18$ year olds than $17$ year olds worked at least $13$ hours each
• E. Most of the students were under $16$ years old

Answer 1

The correct option is D More $18$ year olds than $17$ year olds worked at least $13$ hours each

$\Rightarrow$ In grid we can see, there are only $5$ students who works more than $12$ hours each.

$\therefore$ Option $A$ is incorrect.

$\Rightarrow$ In grid there is not a single student who works exactly $15$ hours.

$\therefore$ Option $B$ is incorrect.

$\Rightarrow$ one $16$ year old student worked exactly $11$ hours not more than that.

$\therefore$ Option $C$ is also incorrect.

$\Rightarrow$ There are $2,$ $17$ year old students who worked at least $13$ hours and there are $3,$ $18$ year old students who worked at least $13$ hours.

$\therefore$ The statement "More $18$ year old than $17$ year old worked at least $13$ hours each" is correct.

$\Rightarrow$ There are only $1$ student who is under $16$ and remaining are above $16$ or $16$ year old. So, option $E$ statement is incorrect,

$\therefore$ Correct answer is option $D$.