GMAT PREP QUESTION

[hey_thr67]

A student worked for 20 days. For each of the amounts shown in the first row of the table, the
second row gives the number of days that the student earned that amount. What is the median amount of
money that the student earned per day for the 20 days ?

Amount earned per day | $96 | $84 | $80 | $70 | $ 48 |

Number of days 4 7 4 3 2


1: $96
2: $84
3: $80
4: $70
5: $48

[eagleeye]

x

[eagleeye]

Hi hey_thr67:

Here's how I solved it under 30 seconds without any calculations.

We have 20 days hence 20 amounts, for median, we need to find the average of amounts on 10th and 11th unit when we arrange them from smallest to largest. Notice that the amounts from right to left are in increasing order (looking from right side 48,70,80,84,96). We are looking to find the average of 10th and 11th amounts.

Now look at the days for the first three we have 2+3+4 = 9 days, so we can safely ignore 48,70,80). For the next two items, amounts are 84 and 84 which of course, averages to 84.

Hence 2 (84)

Let me know if this works