The rightmost non-zero digit in (1001001)(1010101)+(989899)(1001001) -(1001)(989899)-(1010101)(1001) is $a$, and it is followed by $b$ zeroes. Find the ordered pair $(a,b)$.

Creeperhissboom
Apr 22, 2018

#1**+1 **

I think your question is the same as this one, which has been answered:

**https://web2.0calc.com/questions/help_2666**

Guest Apr 22, 2018

#2**+1 **

1001001×1010101 + 989899×1001001 - 1001×989899 - 1010101×1001

1011112111101 + 990889888899 - 990888899 - 1011111101

2002002000000 - 990888899 - 1011111101 =**2,000,000,000,000.**

If you do all the elementary math operations on the above, you should get: **2,000,000,000,000**, or 2 trillion. So, the ordered pair is: a=2 and b=12, or the number of zeros after 2.

Guest Apr 22, 2018

edited by
Guest
Apr 22, 2018

#3**0 **

Oh okay

I got it like 10 minutes after i asked for help. Thanks anyways!

Creeperhissboom
Apr 23, 2018