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- [Instructor] Joey used
0.432 pounds of cheese
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to make mac-and-cheese for dinner,
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and we could also call this
432/1,000 pounds of cheese
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to make mac-and-cheese for dinner.
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Round the amount of cheese
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to the nearest tenth.
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So the amount of cheese once again
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is 0.432 pounds
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and just remember the places here.
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This is 4/10,
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so that's the tenths place.
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This is the hundredths place,
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and that's an S there,
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so tenths, hundredths,
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and this right over here is thousandths,
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thousandths place.
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So we wanna round to the nearest tenth.
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So we're gonna round to the nearest tenth.
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We go one place to the right.
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If it's five or larger,
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we round up.
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This would become a five.
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If it's less than five,
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well, if it's less than five,
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which is the case here,
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we're gonna round down to just 4/10 even.
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So because three is less than five,
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we are going to round down,
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and we're going to get 0.400,
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or we could write that as 0.4,
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or we could write that as 4/10 of a pound.
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Let's do another one.
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Eliza's pet snail traveled
2.197 meters in one day.
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Round the distance to
the nearest hundredth.
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So pause this video and
see if you can do that.
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Round the distance to
the nearest hundredth.
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So it's 2.197.
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This is the hundredths
place right over here,
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and so if we're gonna round
to the nearest hundredth,
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we're gonna go one place to the right.
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If this one place to the right
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is five or greater,
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we're gonna round up,
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and seven is five or greater,
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so we are going to round up .
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Now this is interesting
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'cause if you round a nine up,
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you get to 10,
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but you can't put a
whole 10 right over here.
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So one way to think about it
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is you have a 19 here,
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and so if you round up,
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you're gonna go to a 20,
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or another way to think about it.
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If you round the nine up,
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you're gonna go to the next tenth.
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So this is going to be 2 point,
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you could view this as 19/100
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or 19/100 and 7/1,000,
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and so now we're gonna round up
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to 20/100,
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so 2.20.
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We're rounding to the nearest hundredth,
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which you could write as 2.2,
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but to make it clear
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that you're rounding to
the nearest hundredth,
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you're gonna write 2.20,
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and later in your life,
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this actually might matter
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to actually show what you're rounding to.
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Let's do another example here.
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Cassandra spends 6.75
hours each day at school.
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Round the amount of time
to the nearest hour.
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Alright, so 6.75,
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so you might be a little confused,
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and actually, I encourage
you to pause the video again
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and try to solve it on your own.
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So you might be a little confused
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'cause they're not saying
round it to the nearest tenth
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or hundredth or one or 10 or 100.
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They're saying to the nearest hour,
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but in this case,
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the hour is the ones place.
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So if we're gonna round
to the nearest hour,
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this is another way of saying
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round to the nearest one.
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So we're gonna round to the nearest one.
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We go one place to the right.
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We go to look at the tenths place.
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If it's five or larger,
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we round up.
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Well, seven is five or larger,
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so we round up to the next hour,
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which is going to be seven,
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so seven hours.
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If this was 6.49999,
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once again, if we're
rounding to the nearest hour,
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we go one place to the right.
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It doesn't matter that we
have all these nines here.
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We'd say, hey, look,
four is less than five.
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Therefore, we should round down,
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round down,
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and you would round down to the next hour.
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Well, the next hour that's below 6.499999,
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nine, nine, nine, nine,
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is six hours,
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but in this case, we had a
seven in the tenths place,
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which is definitely greater
than or equal to five,
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and so we'd round up to the next hour,
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which is seven hours.