Question

After an integer is decreased by 2 it falls between 4.9 and -4.9. What is the sum of all the integers that satisfy this condition?

Answer 1

After an integer is decreased by 2 it falls between 4.9 and -4.9. What is the sum of all the integers that satisfy this condition?

Let

x ------> an integer

so

x-2 < 4.9

and

x-2 > -4.9

Solve the system of inequalities

x-2 < 4.9

x < 6.9 -------> interval (-infinite, 6.9)

x-2 > -4.9

x > -2.9 ------> interval (-2.9, infinite)

the solution of the system is the interval (-2.9, 6.9)

possible solutions are

-2,-1,0,1,2,3,4,5,6

their sum is

-2+-1+0+1+2+3+4+5+6=18

the answer is 18