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14 superheroes met on the moon for a top secret gathering fascinating three of them turned out to be evil villains in disguise though how many were real superheroes real superheroes so pause this video and see if you can figure this out now you've had your try let's work through work on it together so 14 superheroes met on the moon so let's write that down 14 met on the moon put a little circle around it like that so 14 men on the moon now of that 14 it they tell us that three of them turned out to be evil villains in disguise so three of them are evil villains so of the 14 we're either dealing with the three evil villains or we're dealing with real superheroes one way to think about it is the 14 are made up of evil villains or real superheroes so this question mark right over here this is the real superheroes this is what we need to figure out and so this relationship could be written in different ways you could write you could write that the three villains plus the question mark real superheroes plus the question mark real superheroes is going to be equal to the total number of characters that met on the moon or you could say well if 3 plus question mark is 14 well then 14 minus 3 minus 3 is going to be equal to question mark is going to be equal to question mark and you see it right over here the 14 is made up of three in question mark so if you get rid of the if you take 14 minus 3 you're just going to be left with the number of real superheroes so what's 14 minus 3 well there's several ways you could do this but one weighs well let's see 14 minus 1 is going to be 13 14 minus 2 is 12 14 minus 3 is 11 so we have 11 is equal 11 is equal to question mark or question mark is equal to 11 or there are 11 real superheroes now let's do one more let's do one more we found many sea monsters in the nearby lake nine of them have stripes five of them have spots how many sea monsters are in the lake how many sea monsters are on the lake so what are they telling us so the total how many sea monsters like this is the total number of sea monsters this is what we're trying to figure out the total number of sea monsters that's how many sea monsters are on the lake and they tell us they tell us that nine of them have stripes nine nine of them have stripes and five of them have spots five of them have spots so all the sea monsters are mate all the sea monsters are going to be the nine that have stripes plus the five that have spots so we could write nine plus five nine plus 5 is equal to question mark is equal to question mark and so what is nine plus five well you might have that memorized already that is 14 or if you don't you could say well see nine plus one is going to be 10 9 plus 2 is 11 9 plus 3 is 12 9 plus 4 is 13 9 plus 5 is 14 so 14 is equal to question mark or how many sea monsters are in the lake 14