The sum of three numbers a, b and c is 60. If we decrease a by 7, we get the value N. If we increase b by 7, we get the value N. If we divide c by 7, we also get the value N. What is the value of N?
a + b + c==60, a - 7==b +7, b + 7==c/7, solve for a, b, c
a ==41/3, b== - 1/3, c==140 / 3
N ==41/3 - 7 ==20/3............(a)
N == - 1/3 + 7==20 /3.........(b)
N==[140/3] /7==20/3.........(c)
