0:00:00.560,0:00:05.830
A recipe for banana oat muffins[br]calls for 3/4 of a cup
0:00:05.830,0:00:07.820
of old-fashioned oats.
0:00:07.820,0:00:10.740
You are making 1/2[br]of the recipe.
0:00:10.740,0:00:13.230
How much oats should you use?
0:00:13.230,0:00:16.550
So if the whole recipe requires[br]3/4 of a cup and
0:00:16.550,0:00:18.630
you're making half of[br]the recipe, you want
0:00:18.630,0:00:20.520
half of 3/4, right?
0:00:20.520,0:00:23.100
You want half of the number of[br]old-fashioned oats as the
0:00:23.100,0:00:24.330
whole recipe.
0:00:24.330,0:00:28.440
So you want 1/2 of 3/4.
0:00:31.010,0:00:35.860
So you just multiply 1/2 times[br]3/4, and this is equal to--
0:00:35.860,0:00:37.550
you multiply the numerators.
0:00:37.550,0:00:40.590
1 times 3 is 3.
0:00:40.590,0:00:42.960
2 times 4 is 8.
0:00:42.960,0:00:43.820
And we're done!
0:00:43.820,0:00:51.885
You need 3/8 of a cup of[br]old-fashioned oats.
0:00:51.885,0:00:54.220
And let's visualize that a[br]little bit, just so it makes a
0:00:54.220,0:00:55.040
little bit more sense.
0:00:55.040,0:00:59.560
Let me draw what 3/4 looks like,[br]or essentially how much
0:00:59.560,0:01:02.400
oats you would need in a normal[br]situation, or if you're
0:01:02.400,0:01:04.060
doing the whole recipe.
0:01:04.060,0:01:06.950
So let me draw.
0:01:06.950,0:01:11.270
Let's say this represents a[br]whole cup, and if we put it
0:01:11.270,0:01:15.040
into fourths-- let me divide[br]it a little bit better.
0:01:15.040,0:01:23.690
So if we put it into fourths,[br]3/4 would represent three of
0:01:23.690,0:01:28.290
these, so it would represent[br]one, two, three.
0:01:28.290,0:01:30.740
It would represent[br]that many oats.
0:01:30.740,0:01:33.240
Now, you want half[br]of this, right?
0:01:33.240,0:01:35.110
Because you're going to make[br]half of the recipe.
0:01:35.110,0:01:39.320
So we can just split[br]this in half.
0:01:39.320,0:01:41.700
Let me do this with[br]a new color.
0:01:41.700,0:01:44.600
So you would normally use this[br]orange amount of oats, but
0:01:44.600,0:01:46.270
we're going to do half the[br]recipe, so you'd want
0:01:46.270,0:01:47.645
half as many oats.
0:01:50.440,0:01:54.930
So you would want[br]this many oats.
0:01:54.930,0:01:56.790
Now, let's think about[br]what that is
0:01:56.790,0:01:59.190
relative to a whole cup.
0:01:59.190,0:02:02.520
Well, one way we can do it is[br]to turn each of these four
0:02:02.520,0:02:05.360
buckets, or these four pieces,[br]or these four sections of a
0:02:05.360,0:02:07.630
cup into eight sections[br]of a cup.
0:02:07.630,0:02:09.000
Let's see what happens[br]when we do that.
0:02:09.000,0:02:13.260
So we're essentially turning[br]each piece, each fourth, into
0:02:13.260,0:02:14.530
two pieces.
0:02:14.530,0:02:16.510
So let's divide each[br]of them into two.
0:02:16.510,0:02:19.340
So this is the first piece.
0:02:19.340,0:02:22.810
We're going to divide it into[br]two right there, so now it is
0:02:22.810,0:02:24.250
two pieces.
0:02:24.250,0:02:26.300
And then this is the second[br]piece right here.
0:02:26.300,0:02:30.390
We divide it into one piece[br]and then two pieces.
0:02:30.390,0:02:32.980
This is the third piece, so[br]we divide it into one, two
0:02:32.980,0:02:35.805
pieces, and this is the fourth[br]piece, or the fourth section,
0:02:35.805,0:02:37.950
and we divide it into[br]two sections.
0:02:37.950,0:02:45.490
Now, what is this as a fraction[br]of the whole?
0:02:45.490,0:02:47.840
Well, we have eight[br]pieces now, right?
0:02:47.840,0:02:50.810
One, two, three, four, five,[br]six, seven, eight, because we
0:02:50.810,0:02:53.380
turned each of the four, we[br]split them again into eight,
0:02:53.380,0:02:56.650
so we have 8 as the denominator,[br]and we took half
0:02:56.650,0:02:57.980
of the 3/4, right?
0:02:57.980,0:03:00.430
Remember, 3/4 was in orange.
0:03:00.430,0:03:02.170
Let me make this very[br]clear because this
0:03:02.170,0:03:04.110
drawing can get confusing.
0:03:04.110,0:03:06.280
This was 3/4 right there.
0:03:06.280,0:03:09.090
So that is 3/4.
0:03:09.090,0:03:19.620
This area in this purple color[br]is 1/2 of the 3/4.
0:03:19.620,0:03:22.020
But let's think about it[br]in terms of the eights.
0:03:22.020,0:03:24.180
How many of these sections[br]of eight is it?
0:03:24.180,0:03:26.910
Well, you have one section of[br]eight here, two sections of
0:03:26.910,0:03:30.820
eight there, three sections[br]of eight, so it is 3/8.
0:03:30.820,0:03:33.460
So hopefully that makes some[br]sense or gives you a more
0:03:33.460,0:03:35.260
tangible feel for what[br]it means when
0:03:35.260,0:03:36.800
you take 1/2 of 3/4.