GMAT Prep questions

[sudi760mba]

(1) If some goes from house to work 22 miles an hour in 9 minutes. How long would it take to cover the same distance in 6 minutes?

(2)In a survey, each student selected from a list of 12 songs the 2 songs that the student liked best. If each song was selected 4 times, how many were surveyed?

(3)Quality control is made by inspecting a sample of 2 lightbulbs from a box of 12?
(6)
(24)
(36)
(66)
(72)

[DWarrior]

1.) V=D/T, D=VT
D=22*9/60 = x*6/60

x = 22*9/6=33mph

2.) 48 total selections, each student allowed 2. 24 students surveyed

3.) What?

[bose]

1 ans 33mph
2-total combinations =12*4 =48, now each pair say ab and ba is same and counted twice so 48/2=24
3-66=12c2

[e.cartman]

How long would it take to cover the same distance in 6 minutes?

why 6 minutes of course!

[sudi760mba]

Originally Posted by sudi760mba

(1) If some goes from house to work 22 miles an hour in 9 minutes. How long would it take to cover the same distance in 6 minutes?

(2)In a survey, each student selected from a list of 12 songs the 2 songs that the student liked best. If each song was selected 4 times, how many were surveyed?

(3)Quality control is made by inspecting a sample of 2 lightbulbs from a box of 12?
(6)
(24)
(36)
(66)
(72)

Thanks for the responses. I understand how to calculate (1) and (3) but I'm still confused on (2).

Is (2) using combinations or permutations? If so, how do break it down step by step?

Thanks!

[deeksha]

PLEASE somebody provide the explanation for (2) a little more clearly