Video Transcript
In a garden, there are 53
roses. There are 19 fewer daffodils than
roses. How many daffodils are there? How many flowers are in the
garden?
What we have here is what we call a
two-step problem. It’s not because we’re being asked
two questions. It’s because to answer the final
question, we have to do two things. We have to answer the first
question to get to the second question. It’s like taking two steps up to
your front door. We have to stand on the first step
to get to the second step. To help us understand what we need
to do to solve this problem, we’re shown some bar models.
Now, bar models don’t give us the
answer, but they do help us understand a problem, understand what we need to do. This problem is set in a
garden. And to begin with, we’re told that
there are 53 roses. Can you see those roses represented
on our first bar model? It’s this blue bar here, isn’t
it? We can see that it’s labeled
53. The next thing we’re told is the
number of daffodils in the garden. Now, we’re not told exactly how
many daffodils there are, but we are given a clue. There are 19 fewer daffodils than
roses. And we can see that this has been
drawn on our bar model too. We can see an orange bar has been
drawn to represent daffodils, but it’s shorter than the blue bar. And we can see the label 19
fewer.
Now, later on, we’re going to be
asked how many flowers are in the garden? So, we’re going to need to add
together the number of roses and the number of daffodils. But at the moment, we don’t know
how many daffodils there are. So, before we do any adding, we
need to complete the first step, and that is to subtract. To find 19 fewer than 53, we need
to find the answer to 53 take away 19. Let’s sketch a blank number line to
help us. We’ll start with the number 53.
Now, we know that 19 can be split
into 10 and nine. So, to begin with, let’s make a
jump of 10 backwards. 53 take away 10 is 43. Now, we just need to take away
nine. The number 43 doesn’t have nine
ones for us to take away. So, let’s take away nine in two
different parts. First, we’ll take away three
because taking three away from 43 is very quick to do, and then we’ll take away
what’s left. Three and six make nine. So, we’ll have to take away another
six. First of all, a jump of three, 43
take away three is 40. Now, we need to take away the other
six. 40 take away six is 34. The number of daffodils is 34. We could even label our bar model
with this number.
And now that we’ve completed our
first step, we can solve the whole problem. We’re asked how many flowers are in
the garden. And the bar model underneath shows
us that the total number of flowers is the same as the number of roses, which is
labeled 53, as well as the number of daffodils. In the first step, we worked out
how many daffodils there are. And so, we now know how to find the
total number of flowers. We just need to add together 53 and
34. We know that 53 is five 10s and
three ones and 34 is three 10s and four ones. Five 10s plus another three 10s
equals eight 10s. And three ones plus another four
ones makes a total of seven ones. And eight 10s and seven ones equals
87.
To find the total number of flowers
in the garden, which was the last thing we were being asked to do, we had to
complete two steps. We knew that there were 19 fewer
daffodils than roses, so we first had to calculate the number of daffodils. 53 take away 19 equals 34
daffodils. Our second step then was to add the
number of daffodils to the number of roses. 53 and 34 make 87 altogether. So, the number of flowers in the
garden is 87.
