# Question 1afaf

Apr 4, 2017

Change from a $5 dollar bill is $75 c e n t s$. #### Explanation: You can obtain $16.4 o z$cereal for $2.79.
That implies $25 o z$ will cost $x. If we keep the $o z$on one side and the $ on the other, we can build an equation to solve for the unknown $x$.

We start with two expressions that we want to have similar results. These are mathematical expressions of the first two lines we wrote above.

16.4oz -> $2.79 25oz ->$x

To complete the equation we can divide one expression by the other and equate them:

(16.4oz)/(25oz) = ($2.79)/x (16.4cancel(oz))/(25cancel(oz)) = ($2.79)/x simplify and then cross multiply

16.4x = 25*$2.79 16.4x =$69.75

x=$4.25 To check the answer for correctness, $25 o z$is about $\frac{1}{3}$more than $16.4 o z$. That means if the approximately $3. were also increased by $\frac{1}{3}$, we should add about another $1. So the total will be around $4.

Then you would receive $5.00 -$4.25 = \$0.75 or 75 cents change from a fiver.