The height of a 12 year old boy increased by 17% last year and by 12% this year. what is the total increase in percent terms?

Evaluate the expression for the given value of the variable 2×(c2-5) for c=4

Seymour is twice as old as cassandra. if 16 is added to cassandra’s age and 16 is subtracted from seymour’s age, their ages become equal. what are their present ages? show !

The sum of the speeds of two trains is 720.2 mph. if the speed of the first train is 7.8 mph faster than the second train, find the speeds of each.