Question

The marks obtained by $19$ students of a class are $27,36,22,31,25,26,33,24,37,32,29,28,36,35,27,26,32,35$ and $28$. Find the inter quartile.

• A. $8$
• B. $9$
• C. $7$
• D. None of the above

Answer 1

Answer: (B)

$9$

On arranging the marks in increasing order. we get,

$22,24,25,26,26,27,27,28,28,29,31,32,32,33,35,35,36,36,37$

Total no. of terms $n=19$

Lower quartile (Q1)$=(\frac{n+1}{4}{)}^{th}$item

$=(\frac{19+1}{4}{)}^{th}=5^{th}term$

$=26$

Upper quartile (Q3) $=3(\frac{n+1}{4}{)}^{th}$item

$=3\times 5={15}^{th}$ item

$=35$

Inter quartile $=35-26=9$

Option B is correct.