Answer:
A similar problem to yours is attached in the picture below. We adjust the data of the problem in the picture to fit your question.
The answer is (3/4)*(3/4)*(1/3) = 3/16 of the girls in the class have long brown hair and green eyes
Step-by-step explanation:
As every condition must contain the set we are studying, we are talking about and AND condition, and thus we need to multiply each term to get the correct result.
3/4 * (3/4) * (1/3) = 3/16
So hmmm, first off, let us use the percentage in decimal format, so 20% is just 20/100 or 0.2 and so on
hmm thus
whatever the amounts of "x" and "y" are, we know they have to add up to 30Litres, thus x + y = 30
and we also know the concentrated amount of pineapple, have to also add up to 7.5 thus 0.2x + 0.4y = 7.5
thus
solve for "x", to see how much of the 20% pure juice will be used
what about "y"? well, y = 30 - x
That would be C....(1 x 10^-1) + (6 x 10^-2) + (9 x 10^-3)