Central value of a set of 180 values can be obtained by
2nd tertile
90th percentile
2nd quartile
9th decile
Quartile: Divides a distribution into 4 equal parts, so the number of intercepts required will be 3, i.e. Q1, Q2, Q3

– So, Zero – Q1 covers 25% values
– Similarly, Q2 – Q1, Q3 – Q2 and 100 – Q3 all cover 25% values each
– Thus, Q2 – Zero, 100 – Q2 and Q3 – Q1 all cover 50% values each
– Q1 divides a distribution in a ratio of 25 : 75 OR 1 : 3
– Q2 divides a distribution in a ratio of 50 : 50 OR 1 : 1, Thus second quartile is equivalent to median
– Q3 divides a distribution in a ratio of 75 : 25 OR 3 : 1.
In the given question, n = 180
Thus Q2 which is equivalent to median, divides a distribution in a ratio of 50 : 50 OR 1 : 1.