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Number, NAP-L4-CA24

An ancient coin is made up of gold and silver in the ratio 1:3.

The coin weighs 21.65 grams.

How many grams of silver are in the ancient coin?

`5.4125` `7.217` `14.433` `16.2375`
 
 
 
 
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`16.2375`

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`text(Ratio)\ 1:3 -> 4\ text(parts)`

`text(1 part)` `= 21.65/4`
  `= 5.4125`

 

`text(Silver weight)` `= 3 xx 5.4125`
  `= 16.2375`

Number, NAP-K4-NC08 SA

The colour cerise is made by mixing red, green and blue paint in the ratio  `13 : 3 : 4`.

What is the volume, in litres, of green paint required if 6 litres of cerise paint is made?

Write your answer as a decimal.

     litres
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`0.9\ text(litres)`

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`text(Ratio)\ 13:3:4`

`=>\ text(Fraction of green paint needed)`

`= 3/{(13 + 3 + 4)}`

`= 3/20`
 

`:.\ text(Volume of green paint)`

`= 3/20 xx 6`

`= 0.9\ text(litres)`

Number, NAP-J4-NC04

In a science experiment, Albert needs to add 60 millilitres of acid to every 2 litres of water.

If Albert only has 0.5 litres of water left, how many millilitres of acid should he add?

`0.15\ text(mL)` `0.6\ text(mL)` `15\ text(mL)` `30\ text(mL)` `120\ text(mL)`
 
 
 
 
 
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`15\ text(mL)`

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`text(Given)\ \ 60\ text(mL)` `=> 2\ text(litres)`
`30\ text(mL)` `=> 1\ text(litre)`
`15\ text(mL)` `=> 0.5\ text(litre)`

Number, NAP-D4-CA30 SA

Michelle makes 7.0 litres of a healthy shake to sell at her cafe.

The table below shows the mixture of ingredients that go into the shake.
 

   

 
How many litres of milk does Michelle need?

   litres
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`2.0\ text(litres)`

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`text(Litres of milk)` `= text(parts milk)/text(total parts) xx 7.0`
  `= 4/14 xx 7.0`
  `= 2.0\ text(litres)`

Number, NAP-E4-NC14

Tony is making a fruit cake.

The recipe says he needs 3 cups of sultanas for every 5 cups of flour.

If 2.5 cups of flour are used, how many cups of sultanas are needed?

`0.5\ text(cups)` `1.5\ text(cups)` `2.5\ text(cups)` `4.5\ text(cups)`
 
 
 
 
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`text(1.5 cups)`

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`text(Strategy 1:)`

`text(2.5 is half of 5 cups of flour, therefore half of)`

`text(3 cups of sultanas is required.)`

`=>\ text(1.5 cups of sultanas needed.)`

 

`text(Strategy 2:)`

`text(Let)\ \ n = text(cups of sultanas needed)`

`n/2.5` `=3/5`
`:.n` `=(3 xx 2.5)/5`
  `=1.5\ text(cups)`

Number, NAP-G4-CA09

The colour orange can be made by mixing 5 litres of yellow paint with 8 litres of red paint.

If 140 litres of yellow paint are used in this mixture, how much red paint is needed?

`text(18 litres)` `text(28 litres)` `text(88 litres)` `text(224 litres)`
 
 
 
 
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`text(224 litres)`

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`text(Let)\ \ x =\ text(litres of red paint needed.)`

`5/8` `=140/x`
`5x` `=140 xx 8`
`x` `=(140 xx 8)/5`
  `=224\ text(litres)`

Number, NAP-I4-CA13

A christmas pudding recipe uses 3 cups of sugar for every 4 cups of sultanas.

Select the correct combination of sugar and sultanas for this recipe.

 
 `1/3` cup of sugar, `1/4` cup of sultanas
 
 `1` cup of sugar, `1.5` cups of sultanas
 
 `1.5` cups of sugar, `2` cups of sultanas
 
 `4` cups of sugar, `5` cups of sultanas
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`text(1.5 cups of sugar, 2 cups of sultanas.)`

Show Worked Solution
`text(Ratio)` `= 3:4`
  `=1.5:2`

 

`:.\ text(1.5 cups of sugar, 2 cups of sultanas is)`

`text(in the correct ratio.)`