Question

Noel’s brother is 3 times as old as Noel. The sum of their ages is less than 20. What’s the oldest age that Noel could be?

Identify:


Strategize:


Set up:


Solve:


Check




please help meeee!!!!

Answer 1

The oldest Noel can be is 6

Explanation:

6x3=18

18<20

Noel: 6

Noels' brother: 18

Answer 2

The oldest age noel can be is 10 because
you set up the equation let’s say noels brother is x so x=3n and the other equation x+n<20 so then you replace x with 3n since there equal to each other so u have 3n+n<20 the you subtract n and 3n by n to eliminate the variable and u end up with 2n<20 and you divide both sides by 2 to get the variable by its self and then you get n<10