1 bag : 3 cookies, 2 lollipops.

3 cookies is not divisible 5. So, multiply by 5.

3 cookies x 5 = 15 cookies (which is divisible by 5)

Lollipops also have to multiply by 5 → 2 x 5 = 10 lollipops.

10 lollipops is not divisible by 3. So, multiply by 3.

10 lollipops x 3 = 30 lollipops.

Cookies also have to multiply by 3→ 15 cookies x 3 = 45 cookies

So 1 bag x 3 x 5 = 15 bags
15 bags have 45 cookies and 30 lollipops.

Cost of 15 bags
= cost of 45 cookies + cost of 30 lollipops

= (45÷5) x $2 + (30÷3) x $5
= 9 x $2 + 10 x $5
= $18 + $50
= $68

$408 ÷ $68 = 6

Number of bags packed
= 6 x 15
= 90

You're partially there.
But 15 cookies ÷ 3 = 5 bags can be filled.
6 lollipops ÷ 2 = 3 bags can be filled.

What you want to do is to make the number of bags the same.

5 bags x 3 = 15 bags
3 bags x 5 = 15 bags

So 15 cookies x 3 = 45 cookies
6 lollipops x 5 = 30 lollipops.