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## Intro to decimals

Current time:0:00Total duration:3:49

# Expressing decimals in multiple forms

CCSS Math: 5.NBT.A.3, 5.NBT.A.3a

## Video transcript

- [Instructor] We're asked
which two of the following expressions have the same value as 8.76? Pause this video and see
if you can figure this out on your own. All right now let's do it together. Before I even look at these
choices, I'm just going to really understand what
this number represents and let me just rewrite it. So we have 8.76 so there's
a couple of ways we could think about it, we can look
at our place values, this right over here this is the
ones place, this right over here this is the tenths place,
and this right over here is the hundredths, hundredths place. And so we could view this as
eight ones and seven tenths and six hundredths or eight
ones plus seven tenths plus six hundredths. Well that's exactly what
they wrote right over here. Eight ones, seven tenths, and
six hundredths, so I would choose that one for sure. Now this second choice
looks like an expanded form, but before I even look at
it let's see how we would think about it over here. If we wanted to essentially
write the same idea but in expanded form, eight
ones is the same thing as eight times one and
actually let me color code it so you see where things are coming from. So eight ones that's the
same thing as eight times one and to that we would add
seven tenths, so that's plus seven times 1/10 so seven
tenths plus and I'll do this in this orange color, six
hundredths so that's plus six times a hundredth, six hundredths. So this would be this number
in expanded form is that what they put right over here,
yes it is indeed what they put right over here, so
I will circle that in. Now if you're doing this on
your own we know that we just picked two answers, but
let's see whether these other forms or let's see if we can
write this in these other forms and see how these might
not be the exact answer. So if we were to write
this out and take out each of the decimal parts, so the
eight ones you'd just write that as eight, the seven
tenths, seven tenths well that would be plus 0.7 this is
seven tenths right over here, this and this and this part
right over here are all equivalent and then last
but not least you have your six hundredths, so plus so
that's our ones, that's our tenths, and then we're in our
hundredths place and we're going to have six of them. So this would be equal to our
original value but that's not what they wrote over here,
they did write eight ones, they did write seven tenths,
but they did not write six hundredths, they wrote
six thousandths here. So we could rule that one out. And then if we were to write
it out in words we would say this is eight eight and
do and in a neutral color, now you might say and seven
tenths and six hundredths, or you could often what's
normally is you express it in the lowest place that
you have or the most precise place that you have so you
could do seven tenths as 70 hundredths or you could view,
you could view this whole thing as 76 hundredths so
it could be eight and 70, 70 six hundredths, hundredths. But what they wrote over
here they did write eight but instead of 76 hundredths,
they wrote eight and 67 hundredths a little tricky
so we would rule that one out as well.