Answer:
60 milligrams
Step-by-step explanation:
just cross multiply! percentages are just fractions of 100. so you can say that 
multiple 75 by x and 45 by 100 and you get
4500=75x
divide both sides by 75 and you get 60
Answer:
mention any one contribution of maiti nepal
Answer:
Four times his sister's age would be 4b. his age is two years less, so we need to subtract 2.
put together, this is 4b - 2.
There is a special kind of substitution which some books call it by comparison.
When the two equations are both
y=some function of x
y=some other function of x, then
we can substitute the second equation into the first giving
some function of x = some other function of x and start solving.
For example,
<span>y = –2x + 8
y = x – 1
substitute second into first
x-1=-2x+8
isolate x on left,
3x=9
x=3
second step is to substitute x=3 into second equation to get
y=x-1=3-1=2
Therefore the solution is (3,2)</span>
