comments on: sat permutations and combinations practice questions - 加拿大vs摩洛哥欧赔 //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/ sat test preparation and information fri, 18 jun 2021 01:42:35 +0000 hourly 1 by: magoosh test prep expert //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-378668 fri, 18 jun 2021 01:42:35 +0000 //www.catharsisit.com/sat/?p=367#comment-378668 in reply to devashis nayak.

hi devashis,

this would be true if the question mentioned that she had worn any of those 5 blouses on tuesday before wednesday and thursday. however, we don’t know this. all we know from the question is that she cannot wear the same blouse on two consecutive days, so we need to come up with the number of options for two days in the week. for example – what if she wore dresses on monday and tuesday? she would still have 5 blouses as an option for wednesday and 4 blouses for thursday. in other words, the question could have easily told us “monday and tuesday” and the answer would be the same. 🙂

]]> by: devashis nayak //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-378343 sun, 06 jun 2021 14:45:20 +0000 //www.catharsisit.com/sat/?p=367#comment-378343 answer to question number 1 is 16 not 20.
the number of ways she can select blouse on wednesday is 4 because she cannot wear one blouse that was used on tuesday. similarly, the number of ways she can select blouses on thursday is 4. total = 4 x 4= 16.

]]> by: magoosh test prep expert //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-192204 tue, 21 jun 2016 11:00:16 +0000 //www.catharsisit.com/sat/?p=367#comment-192204 in reply to anes p a.

hi anes 🙂

yes, you’re correct 😀 let’s look at how to solve this problem to see why. in this question, we’re dealing with permutations with restrictions. a straight forward way to approach these types of problems is to consider the different scenarios. here, we have:

1. green skirt and not green blouse
2. green blouse and not green skirt
3. neither green blouse nor green skirt

we can use permutations to calculate how many different outfits we can have in each of the three situations and then add these three values together to get the total number of possible outfits.

1. green skirt and not green blouse
number of possible skirts: 1 (green)
number of possible blouses: 3 (all minus green)
number of possible shawls: 3 (all)
number of outfits: 1*3*3 = 9

2. green blouse and not green skirt
number of possible skirts: 2 (all minus green)
number of possible blouses: 1 (green)
number of possible shawls: 3 (all)
number of outfits: 2*1*3 = 6

3. neither green blouse nor green skirt
number of possible skirts: 2 (all minus green)
number of possible blouses: 3 (all minus green)
number of possible shawls: 3 (all)
number of outfits: 2*3*3 = 8

total number of outfits: 9 + 6 + 8 = 33 outfits

i hope this helps 🙂

]]> by: anes p a //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-192199 tue, 21 jun 2016 10:50:40 +0000 //www.catharsisit.com/sat/?p=367#comment-192199 dear sir,

i have a kerala psc 2003 question as “different colours 3 skirts, 4 blouse, 3 shawl bought by dhanya. but green skirt and green blouse could not use due to inappropriate look. how many different ways she can wear them?

(a) 36 (b) 34 (c) 33 (d) 35
i select 33 ? is it right ?

reply me”

]]> by: chris lele //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-354 tue, 05 nov 2013 18:54:43 +0000 //www.catharsisit.com/sat/?p=367#comment-354 in reply to samuel phiri.

hi samuel,

sure! in the new few months, i’m sure there will be another lesson on permutations and combinations, one with more questions.

stay tuned!

]]> by: samuel phiri //www.catharsisit.com/sat/sat-permutations-and-combinations-practice-questions/#comment-353 thu, 03 oct 2013 14:56:19 +0000 //www.catharsisit.com/sat/?p=367#comment-353 these are great questions i love them, perhaps you can add more. thank you.

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