Arithmetic Problem

[vongdn]

If it took Carlos 1/2 hour to cycle from his house to the library yesterday, was the distance that he cycled greater than 6 miles? (note: 1 mile = 5280 feet)

(1) The average speed cycled was greater than 16 ft/sec
(2) The average speed cycled was less than 18 ft/sec


ANSWER --> (1) and (2) together are not sufficient.


The trick here is seeing if the greater than and less part of the answer suffices to figure out of he cycled more than 6 miles. But I figured this out by doing the whole equations out, ie converting ft/sec to ft/min, then multiplying by 30 mins, then converting ft into miles. I did this for both statements, but is there a quicker way?

[saurabhmahajan]

what i did was that i converted 1/2 hour into sec i.e 1800 sec

stmt 1) more that 16ft/sec = 16*1800 / 5280
same way for stmt 2.

[deepak123gmat]

According to me answer is C. both together are sufficient. if we consider 17 ft/sec.

[deepak123gmat]

please dont bother. silly assumption.

[diebeatsthegmat]

If it took Carlos 1/2 hour to cycle from his house to the library yesterday, was the distance that he cycled greater than 6 miles? (note: 1 mile = 5280 feet)

(1) The average speed cycled was greater than 16 ft/sec
(2) The average speed cycled was less than 18 ft/sec


ANSWER --> (1) and (2) together are not sufficient.


The trick here is seeing if the greater than and less part of the answer suffices to figure out of he cycled more than 6 miles. But I figured this out by doing the whole equations out, ie converting ft/sec to ft/min, then multiplying by 30 mins, then converting ft into miles. I did this for both statements, but is there a quicker way?

speed is between 16 and 18 so speed can be 16,5 or 17,9
when you multiply 1/2 hour or 1800 second * 16,5 the distance is smaller than 6 miles but when 17,9 or 17,5* 1800 the distance is bigger than 6 miles so its insufficient
E