There are several groups of numbers natural number are counting number,,1,2,3,4,5,6.. whole numbers include 0 as well integers means negative and positive numbers not including decimals =-6,-5,-4,-3,-2,-1,0,1,2,3,4,5... so prime number is a number that cannot be factored out using integers. basically a number that the only factors are 1 and itself exg 3 is prime becuase 3=3 times 1 4 is not prime becuase 2 times 2 is 4 7 is prime becuase the only factors are 1 and 7
negative numbers are numbers less than zero a negative number is like -1,-2,-3,-4,-5,-6,-7,-8,-9,-10... when added, it's like subtraction exg add 3 and -2 together=3+(-2)=3-2=1
Alright so lets start with prime numbers. A prime number is a number that can only be divided evenly by 1 and itself. For example, 7 is a prime number it can only be divided by itself and 1, if it's divided by anything other than 1 and itself, the answer will be a decimal number. 4 is not a prime, because it can be divided by 2.
Now onto negative numbers. Normal numbers exist on a line, starting with 0, all numbers to the left of it are positive, like 1, 2, 3, 4,... , but to the right of zero are the negative numbers ...-4, -3, -2, -1. Negative numbers are the opposite of positive numbers, so that means the larger the number looks, the smaller the quantity is, so -20 is actually smaller than -10. Think of it like this, would you rather owe someone 20 dollars or 10 dollars? A number line with positive and negative numbers would look like .....-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5,........ Notice how the negative numbers count down from left to right, this is because the greater numbers on the number line are to the right and as I said before, the smaller a negative looks, the greater it actually is. I hope all that helped.
So you add 11/15 and 12/15 since the common denominator is already 15 you only need to add the numerator which is 11 and 12 and 11+12= 23 thus you get 23/15
