Natural numbers
A number is divisible by 3 when...
the sum of its digits is a multiple of 3
What is the order of operations?
1.-Parenthesis
2.- Exponent
3. Multiply and division
4. Add and subtract
To divide by 0.5 is the same as multiply by...
2
When are 2 fractions equivalent?
2 fractions are equivalent when they represent the same rational number.
35
Tell me the prime numbers smaller than 31
2,3,5,7,11,13,17,19,23,29,31.
(-9)-(9-11)+(-8)-(10-7)
18
What types of decimal numbers do we have?
Exact decimal, pure repeating decimal, mixed repeating decimal and irrational numbers.
Reduce this fraction 84/210
2/5
Among users of a sport centre, one in ten is over 60 years old, and two in five are between 25 and 60. What fraction of users are 25 and under?
1/2
504=23x32x7
7-2x[(3-8):(-5)+3]=
-1
7.46 x 1000=
7460
2/3x(3/4-1/2)-1/6x(5/6-1/3)=
1/12
Luis spent 3/8 of his money to buy a present. If we know he had 30 € left, how much money did he had in the beginning?
48 €