Verified answer

You can set this up like this:

You have 30 pounds of chocolates - "x" pounds of the first type, and "30-x" of the second type.

The combined chocolates are selling for $1.10 per pound, so the entire batch is $33 (30*1.10 == 33).

If your "x" pounds is the $1.50 chocolates, you get:

1.50x + 0.90(30 - x) = 33

Then, you solve for x. Since I hate dealing with decimals, I'm going to multiply both sides by 10 first:

15x + 9(30 - x) = 330

Expanding the second term:

15x + 270 - 9x = 330

Subtracting 270 from both sides, and combining the x terms:

6x = 60

Dividing through by 6:

x = 10

So, you have 10 pounds of the expensive chocolates, and 30-10=20 pounds of the cheap ones.

You can verify this by adding up what 10 pounds of expensive and 20 pounds of cheap chocolate would cost, and seeing if it's $33 - you get 15+18, so it checks out.

Let C= $1.50/lb. chocolates

Let K=0.90/lb. chocolates

By WEIGHT, C+K=30

By COST, 1.50C+0.90K=30(1.10)

Since C+K=30, C=30-K

Substitute 30-K for C in the second equation to get

1.50(30-K)+0.90K=33

45-1.5K+0.90K=33

-0.6K=33-45

-0.6K= -12

K= -12/-0.6

K=20

Therefore C=30-20, =10

10 lbs. of $1.50 chocolates and 20 lbs. of $ 0.chocolate

Let x be the number of pounds of 1.50 chocolate:

30 * (1.10) = x(1.50) + (30 - x)(0.90)

33 = 1.5x + 27 - 0.9x

0.6x = 6

x = 10

So 10 pounds of $1.50 chocolate were used (and 30-10 = 20 pounds of $0.90)