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Current time:0:00Total duration:2:15

Video transcript

so we're given four different equations here and each of them have a blank and we need to fill in that blank with a missing number so let's do each of these so on the left hand side of this equation we have one plus four and that is equal to so one plus four is the same thing as well one plus four is five if we take four and if you add one more you're going to have five so now we finish that one because one plus four is the same thing as five now here we're saying four plus something is the same thing as five well we just figured out that one plus four or four plus 1 is the same thing as five so four plus one is five so notice that we have the equation four plus 1 is the same thing as five equals means that what's on the left is the same thing as what you have on the right now we have blank plus two is equal to five so what plus two is the same thing as five well three plus two is equal to five or five is equal to three plus two now you go here well now they have three plus blank is equal to five well we already figured it out because three plus two is equal to five so we could write three plus two is equal to five that we could check ourselves and then we could keep going so now we have some subtraction so what's the same thing as nine minus three so if I have nine things and if I were to take away three of them I'm going to have six left nine minus three is the same thing as six ten minus blank is equal to six so what do I have to take away from ten in order to have six left over well if I take far away from ten I'm going to have six left over now something minus one is the same thing as six well seven minus one is going to be equal to six and then we get 8 minus blank is equal to six so how many do have to take away from eight in order to get to six well if I take away one I'm going to get seven if I take away two I'm going to have 6 so 8 minus two is equal to six