Age Probs
posted by Daniella on .
Lisa is 16 years younger than Andy. In 6 year, the sum of their ages id 42. How old is Lisa now?

now, L = A16
In 6 years, (L+6) + (A+6) = 42
so, substitute:
(A16)+6 + A+6 = 42
2A = 46
A = 23
So, Andy is 23, Lisa is 7
In 6 years, they will be 29 and 13, which add to 42 
A candy company packages mixed candies. How much white chocolate selling at $2.75 a pound must be added to 4 pounds of dark chocolate selling at $3.95 a pound to produce a mixture selling for $3.30 a pound?

just add up the cost of each kind. The cost must equal the total.
If there are x pounds of white chocolate needed, then the cost obeys
2.75x + 3.95*4 = 3.30(x+4)
x = 52/11 = 4.73 lbs
Odd answer. Is there a typo somewhere?