Bo is learning words for the GRE.  He got 800 flashcards.  He knew 20% of the words on them.  He has 40 days to learn the rest.  How many words does he need to learn a day?
Бо барои GRE калимаҳоро меомӯзад. Вай 800 флешкарт дорад. Вай 20% калимаҳоро, ки дар онҳо ҳаст, медонад. Вай 40 рӯз барои омӯхтани боқимонда дорад. Вай дар як рӯз чанд калима меомӯзад?
How many words does Bo know? ** He knows 800*.2=<<800*.2=160>>160 words
How many words does Bo need to learn? ** So he needs to learn 800-160=<<800-160=640>>640 words
How many words does Bo need to learn a day? ** That means he needs to learn 640/40=<<640/40=16>>16 words per day
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How many words does Bo know? ** Вай 800*.2=<<800*.2=160>>160 калима медонад  
How many words does Bo need to learn? ** Пас вай бояд 800-160=<<800-160=640>>640 калима омӯзад  
How many words does Bo need to learn a day? ** Ин маънои онро дорад, ки вай бояд 640/40=<<640/40=16>>16 калима дар як рӯз омӯзад  
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