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in 2014 the population of the United States was about 318 million nine hundred thousand people choose the best approximation of the United States population in 2014 so they say three times ten to the eighth people or three times ten to the ninth of people this is a big difference this is a factor of ten this is ten times this right over here so which one's closer so if I were to if I were to round this to the nearest hundred million this would go to three hundred million three hundred three hundred million and three hundred million this is three times 100 million so this is the same thing as 3 times 3 times 100 million and a hundred million we see has eight zeros so this is the same thing as 3 times 10 to the 8th 3 times 10 to the 8th power which they have right over here 3 times 10 tonight that would be 3 billion that would be almost 10 times as large as this so we definitely want to go with this one 3 times 10 to the 8 people is a pretty good approximation this is 300 million people so we're kind of rounding to the nearest hundred million in 2014 the population of the world was about 7 billion 125 million people choose the best approximation of the world population in 2014 well here we're dealing with this is billions here so let me just round to the nearest billion so we could say this is roughly 7 billion 7 7 so approximately 7 billion if we're rounding to the nearest billion and a billion is 10 to the 9th we see we have we have 9 zeros here so this is going to be equal to 7 times 10 to the 9th power which is this right over here this would be 700 million this is less than 1/10 of the actual world population this is 7 billion which is if you're rounding to the nearest billion now how many people there were in 2014 approximately how many times larger was the world population how many times larger was the world population than the United State population in 2014 well what was the world population if we're trying to enter once again they're taking approximately they're saying two twenty two hundred so if we're saying approximately to see the world population if we're using the approximation was seven times ten to the ninth power and the United States population we said it was roughly in 2014 three times ten to the eighth so we could divide this time we could divide this we could divide the world population or approximation of the world population by our approximation of the United States population so our approximation of the world's population divided by the approximation of the United States population three times ten to the eighth power well what's that going to be this is going to be approximately well it is actually going to be exactly 7/3 so we could say so 7/3 that's seven thirds times what's ten to the ninth divided by ten to the eighth power well that's just going to be ten ten to the ninth is ten to the eighth times ten and if we divide that by 10 to the eighth we're just going to be left with ten or if we think about it exponent properties we have the same base ten to the ninth divided by ten to the eighth you can subtract this the exponent in the denominator from the exponent in the numerator so it's going to be ten to the nine minus eight power 10 to the first there's going to be times ten well that's not exactly what they have over here but we see 7/3 this is two and one-third times ten so we could say this is equal to two and one-third times 10 times 10 which is approximately equal to which is approximately equal to two times ten if we're just rounding once again this is all for the sake of roughness which is 20 which is 20 which is that right over there