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#### Resources tagged with Calculating with ratio & proportion similar to Big and Small Numbers in Chemistry:

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### There are 33 results

Broad Topics > Fractions, Decimals, Percentages, Ratio and Proportion > Calculating with ratio & proportion

### Eight Ratios

##### Age 14 to 16 Challenge Level:

Two perpendicular lines lie across each other and the end points are joined to form a quadrilateral. Eight ratios are defined, three are given but five need to be found.

### Investigating the Dilution Series

##### Age 14 to 16 Challenge Level:

Which dilutions can you make using only 10ml pipettes?

### Dilution Series Calculator

##### Age 14 to 16 Challenge Level:

Which dilutions can you make using 10ml pipettes and 100ml measuring cylinders?

### Mixed up Mixture

##### Age 14 to 16 Challenge Level:

Can you fill in the mixed up numbers in this dilution calculation?

##### Age 11 to 14 Challenge Level:

Can you work out which drink has the stronger flavour?

### Exact Dilutions

##### Age 14 to 16 Challenge Level:

Which exact dilution ratios can you make using only 2 dilutions?

### Toad in the Hole

##### Age 11 to 14 Challenge Level:

Is it cheaper to cook a meal from scratch or to buy a ready meal? What difference does the number of people you're cooking for make?

### Using the Haemocytometer

##### Age 14 to 16 Challenge Level:

Practise your skills of proportional reasoning with this interactive haemocytometer.

### The Fastest Cyclist

##### Age 14 to 16 Challenge Level:

Andy is desperate to reach John o'Groats first. Can you devise a winning race plan?

### Nutrition and Cycling

##### Age 14 to 16 Challenge Level:

Andy wants to cycle from Land's End to John o'Groats. Will he be able to eat enough to keep him going?

### Half a Triangle

##### Age 14 to 16 Challenge Level:

Construct a line parallel to one side of a triangle so that the triangle is divided into two equal areas.

### Make Your Own Solar System

##### Age 7 to 16 Challenge Level:

Making a scale model of the solar system

### Triathlon and Fitness

##### Age 11 to 14 Challenge Level:

The triathlon is a physically gruelling challenge. Can you work out which athlete burnt the most calories?

### Conical Bottle

##### Age 14 to 16 Challenge Level:

A right circular cone is filled with liquid to a depth of half its vertical height. The cone is inverted. How high up the vertical height of the cone will the liquid rise?

### Wedge on Wedge

##### Age 14 to 16 Challenge Level:

Two right-angled triangles are connected together as part of a structure. An object is dropped from the top of the green triangle where does it pass the base of the blue triangle?

### Burning Down

##### Age 14 to 16 Challenge Level:

One night two candles were lit. Can you work out how long each candle was originally?

### Tray Bake

##### Age 11 to 14 Challenge Level:

My recipe is for 12 cakes - how do I change it if I want to make a different number of cakes?

### Roasting Old Chestnuts 3

##### Age 11 to 16

Mainly for teachers. More mathematics of yesteryear.

### Retiring to Paradise

##### Age 11 to 14 Challenge Level:

When Charlie retires, he's looking forward to the quiet life, whereas Alison wants a busy and exciting retirement. Can you advise them on where they should go?

### Temperature

##### Age 11 to 14 Challenge Level:

Is there a temperature at which Celsius and Fahrenheit readings are the same?

### Do Unto Caesar

##### Age 11 to 14 Challenge Level:

At the beginning of the night three poker players; Alan, Bernie and Craig had money in the ratios 7 : 6 : 5. At the end of the night the ratio was 6 : 5 : 4. One of them won \$1 200. What were the. . . .

##### Age 14 to 16 Challenge Level:

Two ladders are propped up against facing walls. The end of the first ladder is 10 metres above the foot of the first wall. The end of the second ladder is 5 metres above the foot of the second. . . .

### Number Lines in Disguise

##### Age 7 to 14 Challenge Level:

Some of the numbers have fallen off Becky's number line. Can you figure out what they were?

### At a Glance

##### Age 14 to 16 Challenge Level:

The area of a regular pentagon looks about twice as a big as the pentangle star drawn within it. Is it?

### Bus Stop

##### Age 14 to 16 Challenge Level:

Two buses leave at the same time from two towns Shipton and Veston on the same long road, travelling towards each other. At each mile along the road are milestones. The buses' speeds are constant. . . .

### Contact

##### Age 14 to 16 Challenge Level:

A circular plate rolls in contact with the sides of a rectangular tray. How much of its circumference comes into contact with the sides of the tray when it rolls around one circuit?

### Gift of Gems

##### Age 14 to 16 Challenge Level:

Four jewellers share their stock. Can you work out the relative values of their gems?

### Arrh!

##### Age 14 to 16 Challenge Level:

Triangle ABC is equilateral. D, the midpoint of BC, is the centre of the semi-circle whose radius is R which touches AB and AC, as well as a smaller circle with radius r which also touches AB and AC. . . .

### A Shade Crossed

##### Age 14 to 16 Challenge Level:

Find the area of the shaded region created by the two overlapping triangles in terms of a and b?

### Oh for the Mathematics of Yesteryear

##### Age 11 to 14 Challenge Level:

A garrison of 600 men has just enough bread ... but, with the news that the enemy was planning an attack... How many ounces of bread a day must each man in the garrison be allowed, to hold out 45. . . .

### Straw Scaffold

##### Age 11 to 14 Challenge Level:

Build a scaffold out of drinking-straws to support a cup of water

### Hello Again

##### Age 11 to 14 Challenge Level:

Anne completes a circuit around a circular track in 40 seconds. Brenda runs in the opposite direction and meets Anne every 15 seconds. How long does it take Brenda to run around the track?

### Square Pegs

##### Age 11 to 14 Challenge Level:

Which is a better fit, a square peg in a round hole or a round peg in a square hole?