Answer to Question #137664 in Algebra for Faith

Question

1.the salaries of ayanda,refilwe and danisile are in the ratio 2:3:5.if ayanda's salary is R15000, find danisile's salary.
2.store A is selling 10 rolls of toilet paper for R35.50,while store B is selling 32 rolls for R98.00.write down each unit rate to the nearest cent and indicate the one that is the better deal.

Answer 1

1.

Let $x=$ salary of Refilwe, then we get a proportion:

$2:3=15000:x$

$\frac{2}{3}=\frac{15000}{x}$

$2⋅x=15000⋅3$

$2x=45000$

$x=45000:2$

$x=22500$

Let $y=$ salary of Danisile, then

$3:5=22500:y$

$\frac{3}{5}=\frac{22500}{y}$

$3⋅y=22500⋅5$

$3y=112500$

$y=112500:3$

$y=37500$

Solution: The salary of Danisile is R37500.

2.

Store A:

$Rate=\frac{R35.50}{10rolls}=\frac{R3.55}{1roll}=R3.55$ per roll

Store B:

$Rate=\frac{R98.00}{32roll}=\frac{3.06}{1roll}=R3.06$ per roll

Unit rate of store B is the best deal.

Solution: R3.55 per roll and R3.06 per roll (the best deal).