Question

is 100 a term of A.S 21,32,43 ? What about 1000​

Answer 1

if (the number- first term)/c.d is a whole number , that number is a term of the sequence.

(100-21)/11 = 79/11 is not a whole number

therefore 100 is not a term

(1000-21)/11= 979 /11=89

therefore 1000 is a term of the sequence