<PRE><B>Question 1157081</B>
OneFit,  fitness centre has 100 members 
and grows by 20 members per month 
Lest x be the number of months

growth after x years = 100 +20x

 ByGym has 400 members  loses 10 members per month.

members after x years 400-10x

 For one fit to have the same number of members as ByGym we equate both

100+2x = 400-10x

12x=300

x= 25 

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