SOLUTION: Hello. I'm having some difficulty figuring out the following word problem, Can you help me? A bottle contains 650 mL of fruit punch with a concentration of 50% pure fruit jui

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Question 196219: Hello.
I'm having some difficulty figuring out the following word problem, Can you help me?
A bottle contains 650 mL of fruit punch with a concentration of 50% pure fruit juice. Jill drinks 100 mL of the punch and then refills the bottle with an equal amount of a cheaper brand of punch. If the concentration of juice in the bottle is now reduced to 48%, what was the concentration in the punch that Jill added?
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
If Jill drinks some of the 50% pure fruit juice,
what she drinks has that same concentration
and what is left has that same concentration
What is left is:
ml of 50% pure fruit juice
She filled up the bottle, replacing what she drank
with cheaper drink with ml of unknown
concentration fruit juice.
Let = the ml of pure juice in the cheaper drink
In words, I need to write this equation:
(ml of pure juice I end up with)/(total ml of punch) = 48%

ml
Now the question is: How much of the cheap drink added was water?
There was ml in the bottle before she added it
She added ml of pure juice, so

The rest of the ml bottle must have been water
ml
And the concentration of the cheap drink was

37% is the answer
check: does the fruit drink + water add up to 650?
fruit drink:

water:

OK