SAT word problem

Question

Set S consists of all positive multiples of 5 that are less than 100, and set T consists of all positive multiples of 10 that are less than 100. The median of the numbers in set T is how much greater than the median of the numbers in set S?

They are both 50. Here I'm assuming when you say less than 100 you mean strictly less than 100. — Wintermute, Jun 25 '14 at 16:03
Do you know what a median is? Can you find the median of ${1, 2, 3}$? — Karolis Juodelė, Jun 25 '14 at 16:04

DSinghvi · Accepted Answer · 2014-06-25T16:26:53.897

1

The number of multiples of $5$ which are less than $100$ is $\frac{95}{5}=19$. So, the median is the $\frac{19+1}{2}$-th term, which is $50$.

The number of multiples of $10$ which are less than $100$ is $\frac{90}{10} = 9$. By the same process, the median is $50$.

Therefore, the difference is $0$.

edited Jun 25 '14 at 16:26

answered Jun 25 '14 at 16:06

DSinghvi

565

No, the median of $19$ things is the $\frac {19+1}2=10$th term. You have $9$ below, the median itself, and $9$ above. – Ross Millikan Jun 25 '14 at 16:25
yeah definitely , – DSinghvi Jun 25 '14 at 16:27

SAT word problem

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