Question

Mary, who is 16 years old, is 4 times as old as her brother. how old will mary be when she is twice as old as her brother

Answer 1

Mary will be 24 years old when she will be twice as old as her brother.

Here's how this has been calculated:

If Mary is 16 years old and 4 times older than her brother, her brother's age

= 16/4

=4

Mary’s brother is therefore 4 years old.

Now let’s calculate the difference between Mary and her brother’s age through subtraction:

Mary’s age- her brother’s age= 16-4

=12

Therefore, Mary is 12 years older than her brother

So, for Mary to be twice as old as her brother, the formula will be= 12*2

=24

Therefore, Mary will be 24 years old when she will be twice as old as her brother.