A man is going to paint his house in 3 different colours. If the store offers 20 different colours, how many different combinations can he choose for his house?
+33616 Suppose he was going to paint each of rooms A, B and C a different colour.
1. If he decided that A= red, B=blue and C= green was a different combination from A=blue, B=green and C=red, then there would be smile478's 6840 possibilities.
2. However, the way the question is phrased, it sounds more like he would count these as the same combination of colours, in which case there would only be Chris's 1140 possibilities.
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+128578 We have 20 colors and we want to choose 3 of them....so we have
C(20, 3) = 1140 combinations
+33616 Suppose he was going to paint each of rooms A, B and C a different colour.
1. If he decided that A= red, B=blue and C= green was a different combination from A=blue, B=green and C=red, then there would be smile478's 6840 possibilities.
2. However, the way the question is phrased, it sounds more like he would count these as the same combination of colours, in which case there would only be Chris's 1140 possibilities.
.
