Sheila collects toy cars. she has 4 sports cars for every 11 plain cars. she has a total of 45 cars. how many are sports cars?

2÷6+1/2 to the second power plus one

This is different from the first one can someone me

If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).