Mixing colours

1
Mixing colours
I am learning to compare ratios and proportions.
37
2
Alice and Craig both like to make the drink coke
and raspberry. Alice makes it by adding 2 parts
raspberry for every 8 parts coke (28). Craig
makes it by adding 5 parts raspberry for every 15
parts coke (515).
Whose drink will have the most raspberry taste?
Alice
Craig
You can see Craigs ratio is made up of 20 parts
and Alices ratio is made up of ten. To even this
up we could add another ten parts to Alices.
Obviously 2 will be raspberry and 8 will be coke.
Now lets group the raspberry and coke together
for Alice.
You can now see that Craigs drink would have the
strongest raspberry taste.
3
We could also try turning them into fractions and
then finding an equivalent fraction.
Alice
28 or
Craig
515 or
We can turn Alices proportion ( ) into
twentieths by multiplying it by two.
X2
Alice
Its now easy to see that Craigs drink will have
the strongest raspberry taste.
X2
Craig
4
Millie wants to make green paint by mixing blue
and yellow. It is the relative amount of blue to
yellow that makes the green darker.
Option A 3 parts blue to 1 part yellow (31)
Option B 8 parts blue to 4 part yellow (84)
Option A
Option B
Option A is made up to 4 parts and Option B
is made up of 12 parts.
Lets make Option A three times bigger so we
can compare the two options.
It now easy to see Option A will make the
darker green.
Now lets group the yellow together in Option A
5
Now try these questions on your own.
Which of the blue to yellow ratios below gives
the darkest green?
Click again when you have worked out all your
answers.
4) 36 or 25 5) 23 or 32 6) 47 or 56
1) 23 or 59 2) 14 or 412 3) 22
or 13
Need some more practise? Try pg36 37 of Teacher
Tools Fractions, Decimals and Percentages Book
Numeracy resources