The odometer in Mr. Woshingto's car does not work correctly.

In a school 2/3 of the students study a language of those who study a language 2/5 study french

The graph represents the gallons of water in a water tank with respect to the number of hours since it was completely filled

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).