A subtraction problem can be turned in to an addition problem because of negative numbers. Take 5-2=3 for example. If you change 5-2 into an addition problem then you would but he addition sign and a negative sign on 2. This will then leave you with the problem looking like 5+ -2. If you add 5 and -2 you will still get three.
no. of boys : no.of girls
100 : 140
to get the simplest ratio you gotta divide both with a common factor
Because both 100 and 140 share a common factor of 20
the simplest ratio will be
100/20 : 140/20
5:7
5:7 is the simplest ratio
yo sup??
the sum of trails taken should be less than 25 miles
Black bear=B
Eagle Ridge=E
Doe Run=D
(btw names sound cool XD)
we will now try different combinations
B+E=7 1/2 ++ 10 1/4 which is clearly less than 25
B+D=7 1/2 + 8 3/4 which also less than 25
E+D=10 1/4 + 8 3/4 which is also less than 25
B+D+E=7 1/2 + 10 1/4 + 8 3/4 which is greater than 25
Therefore only the 1st,2nd and 3rd case are possible
Hope this helps.