Mathematical problems (on the division of numbers) The natural numbers that can be divided by both 5 and 7 are arranged in a row from 35 to large. Q: what is the sum of 1993 numbers in this column and the remainder divided by 11?
Count the last term first
(1993-1)*35+35=69755
Then calculate the sum
(35+69755)*1993/2=69545735
The remainder of 69545735 divided by 11 is
(5+7+4+9)-(3+5+5+6)=6
6 is the remainder