Hannah is 1 year old today.
Step-by-step explanation:
Let,
Hannah = x
Biff = y
According to given statement;
y = x+25 Eqn 1
In four years;
y+4 = 6(x+4) Eqn 2
Putting value of y from Eqn 1 in Eqn 2;
Dividing both sides by 5
As x is age of Hannah, therefore,
Hannah is 1 year old today.
Keywords: linear equations, substitution method
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