Page 25 - Math Smart - 7

Investigate

lO Spotlight
Use the tests of divisibility to investigate which of the following numbers
can divide 2520 exactly.
Divislbiiity rule for
Seven
3 4 5 6
Subtract twice the
last digit from the
8 9 10 100
number formed by the
remaining digits.
Is 651 divisible by 7?
65-(1 X 2) = 63

Since 63 is divisible by 7,
Check My so is 651.
Understanding
Divisibility rule for
Eleven
O Match the number with the correct test of divisibility. Subtract the last digit

from the number
A number is divisible by this number formed by the
if the sum of its digits is a multiple remaining digits.
of 9.
Is 396 divisible by 11?
3 A number is divisible by this number
39-6 = 33
if its last two digits are 00.
Since 33 is divisible by
4 A number is divisible by this number
11, so is 396.
if the number formed by its last three
digits is a multiple of 8.

5 A number is divisible by this number
if the last digit is an even number.

6 A number is divisible by this number
if its last digit is 0.

8 A number is divisible by this number
if it is divisible by 2 and also by 3.

9 A number is divisible by this number
if the number formed by its last two Being a multiple of 3
digits is divisible by 4. means the number is also

10 A number is divisible by this number divisible by 3. Being a
multiple of 8 means it is
if the sum of its digits is a multiple
of 3. divisible by 8.
100 A number is divisible by this number
if its last digit is 0 or 5.