Question

(2 + x ) + ( 3 + x ) + ... +(20 + x )=370

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Answer 1

(2 + x ) + ( 3 + x ) + ... +(20 + x )=370

(2+3+...+20).x=370

209.x=370

x=370:209

x= 370/209

Answer 2

(2+x)+(3+x)+...+(20+x)=270

x(2+3+...+20)             =270

x .(209)                     =270

x                              =270/209