a) find the next two term in the sequence: 1; 4; 9; 16; 25;....;.....;
Answer: 
b) find the smallest two-digit number whose number is 7 times the sum of its digits? 
Answer:

A 6 digit number begins with the digit 8.The number with divisible by 9 and all digits of the number are different.What is the possible smallest value of this number?

1) Fill the mussing number. A cube has.....vertices

2) Fill the missing number. We're in the....st century

3) Ther are only two 2-digit numbers that are a multiple of 7 and the sum of thetr two digits is 10. Find the sum of these two 2-digit numbers: 70,119,140,21

4) The fourth power of 3 is...

5) Twice the square of 3....

6) The number of ethnic group in Vietnam?

7) The perimeter of 4cm square egde in cm?

Câu 9:
The average mass of a group of children is 47kg. If  of the number of children are girls and their average mass is 39kg. Find the average mass of the boys.
Answer: The average mass of the boys is kg
 

Câu 10:
A 6-digit number begins with the digit 8. The number is divisible by 9 and all digits of the number are different. What is the possible smallest value of this number?
Answer: 

A 4-digits number is divisble by all of the numbers from 1 to 10 ưithout any remainder .

find the smallest possible value of the 4 - digit number 

the sum of the digits of a two-digit number is 11. when you reverse its digits you decrease the number by 9 . Find the number

When a particular six-digit number is multiplied by 2, 3, 4, 5 and 6 respectively, each of the
products is still a six-digit number with the same digits as the original number but in a different
order. Find the original number.

Form the smallest 5 – digit odd number using all the digits below.
9 0 6 5 1
Answer: 

Find all natural numbers having two digit , knowing that twice the units digit 1 more than the ten digit , and if we write that two digits in reverse order, we get a new number which is 27 less than the old one