you can use the distributive property
goes like this
a(b+c)=ab+ac
so what you do it split a number up to make it easier
so in this case you can have 3
a(b+c+d)=ab+ac+ad
so
we can spit 449 into 400+40+9
so
5(400+40+9)=
(5)(400)+(5)(40)+(5)(9)=
2000+200+45=
2245
tada