(20 X 19)/2 = 190 Rationale: Each of the twenty unique objects can be paired with any other one of the objects to make 20 X 19 ordered pairs. However, each such pair will not be uniquely different from the pair with the same objects selected in opposite order. Therefore, 20 X 19 must be divided by 2.
20 of them
The Ordered Pairs are 1x20, 2x10, and 5x4.
20,110,25,4
20....or maybe 18
Celsius measures temperature, not objects.
20 has 3 factor pairs. Pairs are (1,20), (2,10) and (9,9)
Simplify the problem a bit. You have 20 dots and you want to connect pairs of dots, so you're looking for how many unique sets of 2 objects you can choose from 20 distinct objects. Thus you have 20[[Choose]]2 = 20!/(18!2!) = 10*19 = 190 such sets, which correspond to 190 distinct lines. However, there are 20 lines connecting the edges of the 20-sided shape, so we actually have 190 - 20 = 170 lines not corresponding to edges.
3 pairs
There are 3 factor pairs of 20: 1 x 20, 2 x 10 and 4 x 5.
Three of them.
I have 20.
covers over 20 pairs
3 pairs of factors. They are: 1 and 20 2 and 10 4 and 5 Pairs of factors are numbers that you multiply together to make that number, e.g. 4x5=20. Trust me I'm a teacher!
There are 10 pairs of two students in 20 students
20 of them
The factor pairs of 20 are: 20,1 / 10,2 / 5,4
20