How do you calculate 999 multiply 999 plus 998 plus 1 with an easier way?

Answer 1

Easier way than what?

I presume you mean long multiplication of 999 by 999, adding 998 and adding 1.

• One way:

999 = 1000 - 1

⇒ 999 x 999 + 998 + 1 = (1000 - 1) x (1000 - 1) + 998 + 1

= 10002 - 2 x 1000 + 1 + 998 + 1

= 1000000 - 2 x 1000 + 1000

= 1000000 - 1000

= 999000

• Another way:

998 + 1 = 999

⇒ 999 x 999 + 998 + 1 = 999 x 999 + 999

= 999 x (999 + 1)

= 999 x 1000

= 999000