There are 10000 such codes. Each of the numbers 0-9 can be in the first position. With each such first digit, each of the numbers 0-9 can be in the second position. With each such pair of the first two digits, each of the numbers 0-9 can be in the third position. etc.
9
24
In 2 digit numbers : 9, In 3 digit numbers : 18 + 162 = 180, In 4 digit numbers : 2187 + 486 + 27 = 2700, total = 9 + 180 + 2700 + 4 = 2893 simply 2 means:9 3 means:9*2=18 add one 0 so:180 4 means:9*3=27 add two 0 so:2700 then 10000 take four 0:4 total = 9 + 180 + 2700 + 4 = 2893 BY ASHOKKAVI MCA
1,000. The list looks just like the counting numbers from 000 to 999 .
9
-9
the line which divides the number into 2 equal halves is called symmetry in numbers example:- in digits 0 to 9 the symmetry of numbers are 0, 1, 3, 8.
8
for digits 0 to 9 0,1,3,8 have lines of symmtery
10
They are: 8 and 0
11
0, 1, and 8 have symmetry. (:
It depends on how you write them. For example, 2 written here has no symmetry. Where 2 on an LCD display (eg on an elevator/lift would have rotational symmetry) Usually 0 and 8 have both horizontal and vertical symmetry.
8 has lines of symmetry.
2, 4, 5, 6, 7 and 9. Also, in some fonts (such as in this one), 1, and less frequently 3.