Answer:
The picture
Step-by-step explanation:
Use the supplementary theorem and corresponding theorem. :)
The answer would be D. 200 - 20d.
This is because the question asks for pages left after reading for "d" (however many) hours. Since the book has 200 books, you'd subtract from that number since it's the "starting number" of pages. If he reads 20 pages per hour, you would multiply those together to get how many he has read, then subtract that number from 200, to get the amount of pages left.
I hope this helps!
Answer:
Each pitcher has the same fraction of the other drink.
Step-by-step explanation:
After 1 cup of tea is added to x cups of lemonade, the mix has the ratio 1:x of tea to lemonade. So, the fraction of mix that is tea is 1/(x+1).
The 1 cup of mix contains 1/(x+1) cups of tea and so x/(x+1) cups of lemonade. When that amount of lemonade is added to the tea, it brings the proportion of lemonade in the tea to (x/(x+1))/x = 1/(x+1), the same proportion as that of tea in the lemonade.
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You can consider the degenerate case of one cup of drink in each pitcher. Then when the 1 cup of tea is removed from its pitcher and added to the lemonade, you have a 50-50 mix of tea and lemonade. Removing 1 cup of that mix and putting it back in the tea pitcher makes there be a 50-50 mix in both pitchers.
Increasing the quantity in each pitcher does nothing to change the fact that the mixes end up in the same ratio:
tea:lemonade in Pitcher 1 = lemonade:tea in Pitcher 2
