Answer:
Betty is 15.
Mike is 5.
Step-by-step explanation:
We can let Betty's age be b and Mike's age be m.
Since Betty's age is 3 times of Mike, then
[tex]b=3m[/tex]
In 5 years, the age of Betty and Mike would be [tex]b+5[/tex] and [tex]m+5[/tex] respectively.
Since Betty is 2 times as old as Mike then, then [tex]b+5=2(m+5)[/tex].
We know that [tex]b=3m[/tex], so we can substitute that:
[tex]3m+5=2(m+5)[/tex]
Expand:
[tex]3m+5=2m+10[/tex]
Subtract 5 from both sides:
[tex]3m+5-5=2m+10-5[/tex]
[tex]3m=2m+5[/tex]
Subtract 2m from both sides:
[tex]3m-2m=2m+5-2m[/tex]
[tex]m=5[/tex].
Mike is 5 years old.
Since Betty is 3 times as old as Mike, Betty's age is [tex]5*3=15[/tex]