Question #9c85d

1 Answer
Jun 17, 2016

31.46

Explanation:

Per day #2.25#

For 14 days #->14xx2.25#

I am going to show you a method that is easy to do in your head for some numbers. Some others are not so easy. The explanations takes longer than actually applying the approach.

Split up the 14 into 10 + 4

We multiply 2.25 first by 10 and remember the answer
We then multiply 2.25 by 4 like this: double it then double it again.
Now add the two numbers>

#2.25xx10=22.5#

#2.24xx2" "=" "4.48" " |->" " 4.48xx2" "=" "8.96#

#22.50#
#ul(color(white)(.)8.96) +#
#31.46#