John is 10 years old. His sister is twice his age. When he is 50 years old, how old will his sister be?
Ҷон 10 сол дорад. Хоҳараш ду баробари синнаш аст. Вақте ки ӯ 50 сола мешавад, хоҳараш чанд сола хоҳад буд?
How old is John's sister? ** His sister is 10*2= <<10*2=20>>20 years old
How old is John's sister? ** Their age difference is 20-10= <<20-10=10>>10 years
How old will John's sister be when he is 50? ** Therefore when he is 50 she will be 50+10= <<50+10=60>>60 years old.
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How old is John's sister? ** Сисми Ҷон 10*2= <<10*2=20>>20 сол дорад  
How old is John's sister? ** Фарқи синнашон 20-10= <<20-10=10>>10 сол аст  
How old will John's sister be when he is 50? ** Аз ин рӯ, вақте ки ӯ 50-сола мешавад, ӯ 50+10= <<50+10=60>>60 сол хоҳад буд.  
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