cách làm:
dãy trên có số các số là:
( 99 - 10) : 1 + 1 = 90
tổng là:
( 99 + 10) x 90 : 2 = 4905
vậy tổng của tất cả số tự nhiên có 2 chữ số là: 4905
The sum of the digits of all 2-digit numbers is .............
If B is not divisible by 24 and B is the greatest 5 - digit number that the sum of the sum of all digits is 21 then B = ?
What is the sum of all digits in final result when
1+11+111+…+11…111+11+111+…+11…11 (1010 digit 11s)
is computed?
Answer: The sum of all digits in final result is
If B is not divisibly by 24 and B is the greatest 5 - digit number that the sum of all digits is 21 then B = ................
If B is not divisible by 24 and B is the greatest 5 - digit number that the sum of all digits is 21 then B= ?
Given 4 digits: 4, 6, 2, 0.
What is the difference of the largest and the smallest 4-digit numbers that can be formed from these digits. Use each digit only ones.
Answer: The difference is
Using each of the digits 2, 3, 5 and 6 exactly once, form two 2 – digit numbers. What is the difference between the largest possible product and the smallest possible product of two such numbers ?
Using each of the digits 2, 3, 5 and 6 exactly once, form two 2 – digit numbers. What is the difference between the largest possible product and the smallest possible product of two such numbers
Choose 3 digits from 8, 6, 0, 5, 2 and 1 to form 3-digit numbers. How many odd numbers
are there? (The repetition of digits is not allowed)giúp me với
