The probability of rolling a number less than  3
3
on a number cube is 
2
6
.
2
6
.
jennifer rolls a number cube 
60
60
times. How many times should jennifer expect to roll a number less than 
3
?
3
?

A) Original price : y =10.x
Cheaper brand : y = 7x
The original box is $3 more than the cheap one. Proof:
Suppose 1 box is bought of each (x=1),original will cos10 & the cheaper $7
b) Each time he buys a cheap brand he save $3 ($10-$7), on 5 cheap boxes, he would save $3 x 5 boxes = $15