Question

Jane is 3 years older than mary, and mary is twice as old as kay. if kay is x years old, how old is jane?

Answer 1

The answer is y = 2x + 3.

x - Kay's age
y - Jane's age
m - Mary's age

Jane is 3 years older than Mary: y = m + 3
Mary is twice as old as Kay: m = 2x

y = m + 3
m = 2x

Substitute m in the first equation:
y = 2x + 3

Answer 2

2x +3 years old is Jane

Explanation:

As per the statement:

If Kay is x years old.

Mary is twice as old as Kay.

then;

Mary = 2x years old

It is also given that Jane is 3 years older than mary

⇒ Jane = 2x + 3

Therefore, 2x +3 years old is Jane