Evelyn is making a candy that contains 25% dark chocolate and the rest milk chocolate. the candy has 3 pounds of milk chocolate. part a: write an equation using one variable that can be used to find the total number of pounds of dark chocolate and milk chocolate in the candy. define the variable used in the equation. part b: how many pounds of dark chocolate are present in the candy? show your work.

Candy >  contains 25% dark chocolate
so 
            > contains 75% milk chocolate > 3 pounds
X=the total number of pounds of dark chocolate and milk chocolate in the candy
a=number of pounds of dark chocolate
b=number of pounds of milk chocolate
X=a+b
a=X*0.25
b=X*0.75

X=X*0.25+b > X=(4/3)b

1) using one variable  b
the equation is  X=(4/3)b
b=number of pounds of milk chocolate

2) How many pounds of dark chocolate are present in the candy? 
X=(4/3)b > X=(4/3)*3=4 pounds is the total
X=4 pounds
b=3 pounds
a=X-b
pounds of dark chocolate=4-3=1 pound