First find the number of girls in her class.
29 student - 21 boys = 8 girls
So, the ratio of girls to boys is:
8 girls:21 boys
Or just:
8:21
answer: 8:21
Since it's a multiple of 24, it has to be a multiple of the factors of 24.
Factors of 24:
2,3,4,6,8,12
You can use some of this knowledge to help create the number.
Since the # needs to be a multiple off 2, the last digit needs to be an 8
All numbers that are multiples of 3 have the property that all of their digits added together have to be a number that is evenly divisible by 3.
so your number will look like:
_ _ _ _ _ 8
so start trying combinations for the other 5 digits that give you a number that is a multiple of 3: 3,6,9,12,15, ect. If you can't find one, then it's impossible
Perpendicular lines have slopes that are negative reciprocals. example: line a has a slope of 2/3, line b has a slope if -3/2 if they are perpendicular.
