the gender of the kids does not matter so it can be discarded.
you add up how many boys and girls in the class to make a total of 50 kids
your 100% is 50
meaning 40% of 50 is 20
so if 20 kids took the bus to school then 30 did not take the bus.
1 meter = 1000 millimeters
I'll go with A and B
Hope this helps
-10x + 1.5 because you get rid of the parenthesis so -2 times 5 is -10 ( -10x ) and then -2 times -0.75 equals positive 1.5 due to two negatives canceling out to positive hope this helped!