Question

3. At a poster shop, Han paid $16.80 for 2 large posters and 3 small posters of his

favorite band. Kiran paid $14.15 for 1 large poster and 4 small posters of his fa
TV shows. Posters of the same size have the same price.
Find the price of a large poster, l, and the price of a small poster, s.

Answer 1

small posters cost $2.30 each

large posters cost $4.95 each

Explanation:

Let

price of large poster be "l", and

price of small poster be "s"

$16.80 for 2 large and 3 small, we can write:

2l + 3s = 16.80

Then,

$14.15 for 1 large and 4 small, we can write:

l + 4s = 14.15

We can write this as:

l = 14.15 - 4s

Now we substitute this expression for "l" into first equation and solve for s first:

`2l+3s=16.80\\2(14.15 - 4s)+3s=16.80\\28.30-8s+3s=16.80\\5s=11.5\\s=2.30`

small posters cost $2.30 each

Now, we know l = 14.15 - 4s, so

l = 14.15 -4(2.30)

l = 4.95

large posters cost $4.95 each