Brian can only hold his breath underwater for 10 seconds.  He wants to get better, so he starts practicing.  After a week, he's doubled the amount of time he can do it.  After another week, he's doubled it again from the previous week.  The final week, he's increased it by 50% from the previous week.  How long can Brian hold his breath for now?
Брайан танҳо метавонад нафасашро дар об барои 10 сония нигоҳ дорад. Вай мехоҳад беҳтар шавад, бинобар ин, ӯ оғоз мекунад ба машқ кардан. Пас аз як ҳафта, ӯ миқдори вақти, ки метавонад ин корро кунад, ду баробар мекунад. Пас аз як ҳафтаи дигар, ӯ онро боз ду баробар мекунад. Дар ҳафтаи ниҳоӣ, ӯ онро 50% аз ҳафтаи қаблӣ зиёд мекунад. Ҳоло Брайан чанд вақт метавонад нафасашро нигоҳ дорад?
How long can Brian hold his breath for after the first week? ** At the end of his first week, Brian now has doubled his initial time of 10 seconds to 10*2=<<10*2=20>>20 seconds
How long can Brian hold his breath for after the second week? ** At the end of his second week, Brian doubled the previous week's time of 20 seconds to 20*2=<<20*2=40>>40 seconds
How long can Brian hold his breath for after the third week? ** At the end of his third week of practice, Brian adds another 50% of 40 seconds to his time so 40*.5= <<40*.5=20>>20 seconds added
How long can Brian hold his breath for now? ** Having added 20 seconds to his time from his second week, Brian can now hold his breath for 40+20= <<20+40=60>>60 seconds
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How long can Brian hold his breath for after the first week? ** At the end of his first week, Brian now has doubled his initial time of 10 seconds to 10*2=<<10*2=20>>20 seconds  
How long can Brian hold his breath for after the second week? ** At the end of his second week, Brian doubled the previous week's time of 20 seconds to 20*2=<<20*2=40>>40 seconds  
How long can Brian hold his breath for after the third week? ** At the end of his third week of practice, Brian adds another 50% of 40 seconds to his time so 40*.5= <<40*.5=20>>20 seconds added  
How long can Brian hold his breath for now? ** Having added 20 seconds to his time from his second week, Brian can now hold his breath for 40+20= <<20+40=60>>60 seconds  
#### 60  

Чанд вақт Брайан метавонад нафасашро пас аз ҳафтаи аввал нигоҳ дорад? ** Дар охири ҳафтаи аввал, Брайан акнун вақти ибтидоии 10 сонияшро ду баробар кардааст, то 10*2=<<10*2=20>>20 сония  
Чанд вақт Брайан метавонад нафасашро пас аз ҳафтаи дуюм нигоҳ дорад? ** Дар охири ҳафтаи дуюм, Брайан вақти ҳафтаи қаблиро, ки 20 сония буд, ду баробар кард, то 20*2=<<20*2=40>>40 сония  
Чанд вақт Брайан метавонад нафасашро пас аз ҳафтаи сеюм нигоҳ дорад? ** Дар охири ҳафтаи сеюми машқ, Брайан 50% и 40 сонияро ба вақти худ илова мекунад, пас 40*.5= <<40*.5=20>>20 сония илова шуд  
Чанд вақт Брайан метавонад ҳоло нафасашро нигоҳ дорад? ** Пас аз илова кардани 20 сония ба вақти худ аз ҳафтаи дуюм, Брайан акнун метавонад нафасашро барои 40+20= <<20+40=60>>60 сония нигоҳ дорад  
#### 60  