13/ 52 = 1/4 chances.
There are 13 spades and 52 cards. You divide the spades and cards in the deck to find your chances of drawing one.
You have a 25% chance of getting a spade.
Now you put it back. Since you put it back, you still have the same number of cards and the same number of spades. So when you divide 13/52 again, the numbers are still the same. 1/4. 25% chance.
So, you still have a 25% chance the second time around.
3-7 is -4 so it becomes -4x=4 divide both sides by 4 to get -x=-1 a lot of teachers dont like that negative x so you can also divide by -1 again to make it x=1
hope it helps
How ever many times it goes into 100
