Given a sequence 2, x, 7…….

• that contains a constant such that the number is obtained by adding the previous number and the constant. Find x.

Constant = c

x= 2+c——(1)

7=x+c——-(2)

(1)-(2)

x-7=2+c-x-c

x+x=2+7

2x=9

x=9/2(Answer)

(1)—-

9/2-2=c

c= (9-4)/2

c=5/2

2, (2+ 5/2), ( 2+5/2 + 5/2)= 7 ………….

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