Question

check my answer? will medal. Q) How many three color patterns can be made using the colors in the rainbow: red, orange, yellow, green, blue, indigo, and violet if the color can only be used once?
my answer) 42?

Answer 1

I am assuming that the order of the 3 colours is not important.
then the number required is the number of combination of 3 from 7.

Answer 2

this is 7 *6*5
------ = 35
3*2*1

Answer 3

thank you @cwrw238

Answer 4

yw