Question

how many three digits are divisible by 7

Answer 1

105, 112, 119,......994

a=105, d= 7

994 = a+(n-1)d
994= 105+(n-1)7
994 - 105 = (n-1)7
889 = (n-1)7
n-1= 889÷7
n-1= 127
n= 128