You use division
over 2 or 4 or 3 or 5 or 7 and so on
in this case 2 is good
64 = 2 * 2 * 2 * 2 * 2 * 2 ( use division) = 2^6
16 = 2 * 2 * 2 * 2 = 2^4
number reminder
64 0
32 0
16 0
8 0
4 0
2 0
1 1
so 64 = 2^6 (number of zeros) no reminder
First you divide $4000 by 160 to see how much each book costs. Then you multiply 2 times the cost for each book and subtract that from $4000.
$4000/160= $25
$25=1 book
So if the store gives away 2 books that's $50 dollars. $4000-$50 equals 3,950
First of all, we need to deduce the price of a single camera:

Now, we know that he profits 36 dollars from each camera. So, we are asking: which percentage of 150 is 36? We have

This equation literally says: 36 is x-percent of 150. And we need to solve for x:
