Posted by Gabby ( 5 grade) on Monday, January 30, 2012 at 4:10pm.
I would divide it out and see.
or
write down the number without the last digit
29
subtract twice the digit you skipped
29
-2
----
27
is 27 divisilbe by 7 ?
no ? , then neither was 291
for large numbers checking for divisibility by 7,
repeat the above process until you can tell.
Not very practical, but it works !!!
why 2 if the end digit is 1?
notice I said, "twice" the number skipped.
2x1 = 2
i dont get it i want ms sue to help me!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
<g>
Reiny is a REAL math teacher; I'm not.
I'd just divide 291 by 7.
WOW I BELIEVED IN YOU:P
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