Answer:
So, cost of small size is $7 and cost of large size is $13.
Explanation:
Let cost of each small size - x, cost of each large size - y
By the question,
3x + 14y = 203
11x + 11y = 220
From the first equation, we get,
3x + 14y = 203
or, 3x = 203 - 14y
so, x = (203 - 14y)/3
Substituting x's value in second equation :-
11x + 11y = 220
or, 11 { (203 - 14y)/3 } + 11y = 220
or, {2233 - 154y}/3 + 11y = 220
or, { 2233 -154y + 33y} = 660
or, 2233 - 121y = 660
or, 121y = 2233 - 660
or, 121y = 1573
so, y = 1573/121
so, y = 13
Now,
As we know,
x = (203 - 14y)/3
or, x = ( 203 - 14 × 13)/3
or, x = (203 - 182)/3
so, x = 21/3
so, x = 7
So, cost of small size is $7 and cost of large size is $13.