Given:
Total number of flower they buy = 29 stems
Total cost = $120.94
Lilies cost = $3.42 per stem
Peonies cost = $4.78 per stem
To find:
The number of lily stems and peony stems did they buy.
Solution:
Let number of lily stems = x
Number of lily stems and peony stems = y
According to given information,
...(i)
...(ii)
From (i) and (ii), we get




Divide both sides by -1.36.


Put x=13 in (i).
Therefore, number of lily stems is 13 and number of lily stems and peony stems is 16.