Ok so first you have to put the numbers in order of least to greatest:
1, 7, 12, 14, 15, 17
Next you find the median of the numbers or middle:
1, 7, 12 | 14, 15, 17
Then you find the median of both halves:
1 {7} 12 | 14 {15} 17
So the first quartile is 7 and the third quartile is 15
