Ratios

fliss1992

I have a Key Stage 3 book, yet it doesn't tell me anything about how to work out Ratios..

The ratio of weight of Andy to Jan is 7:5. Jan has a weight of 95kg, how much does Andy weigh?

In a recipe the ratio of flour to butter is 2:3. How much flower is needed to mix with 240g of butter?

Can someone explain please..

Reply 1

TenOfThem

18

Original post by fliss1992

I have a Key Stage 3 book, yet it doesn't tell me anything about how to work out Ratios..

The ratio of weight of Andy to Jan is 7:5. Jan has a weight of 95kg, how much does Andy weigh?

A:J = 7:5

Every 7 kg Andy weighs means that Jan weighs 5kg

So if Andy weighed 42kg (6x7)
Then Jo would weigh 30kg (5x5)

OP

I'm still confused

Original post by fliss1992

I have a Key Stage 3 book, yet it doesn't tell me anything about how to work out Ratios..

The ratio of weight of Andy to Jan is 7:5. Jan has a weight of 95kg, how much does Andy weigh?

In a recipe the ratio of flour to butter is 2:3. How much flower is needed to mix with 240g of butter?

Can someone explain please..

A:J
7:5
?:95

5 x 19 = 95
So we do 7 x 19 to get your answer

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Reply 4

fliss1992

OP

2

but where do you get the 19 from?

Reply 5

2710

18

Original post by fliss1992

but where do you get the 19 from?

95 / 5

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Reply 6

2710

18

Original post by fliss1992

but where do you get the 19 from?

A:J
7:5
?:65

Just to see if you get it. What would be andy here? What you do to one side, you do to the other

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Reply 7

fliss1992

OP

2

133 would be the answer?

Reply 8

2710

18

Original post by fliss1992

133 would be the answer?

Nope. You are using the 19 from the last question.... Its not 19 anymore.

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Reply 9

SianO

Original post by fliss1992

I have a Key Stage 3 book, yet it doesn't tell me anything about how to work out Ratios..

The ratio of weight of Andy to Jan is 7:5. Jan has a weight of 95kg, how much does Andy weigh?

In a recipe the ratio of flour to butter is 2:3. How much flower is needed to mix with 240g of butter?

Can someone explain please..

Eg ..
Flour: Butter
2:3
?:240g

240/3 = 80 ( =1)
So to get 2 .. 2 x 80 =160
160:240

I Hope this helps :smile:

Reply 10

SianO

When you know the amount of one of the ratios, divide it by the ratio number given to find 1. Then multiply the answer by the other ratio amount.

Reply 11

fliss1992

OP

2

5 x 19 = 95
So we do 7 x 19 to get your answer

you said here do 5 x 19 = 95
then 7 x 19 to get your answer this equals 133

so what is it...

Reply 12

2710

18

Original post by fliss1992

5 x 19 = 95
So we do 7 x 19 to get your answer

you said here do 5 x 19 = 95
then 7 x 19 to get your answer this equals 133

so what is it...

In my new question, I put 65, not 95.

A:J
7:5
?:65

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Reply 13

TenOfThem

18

Original post by fliss1992

5 x 19 = 95
So we do 7 x 19 to get your answer

you said here do 5 x 19 = 95
then 7 x 19 to get your answer this equals 133

so what is it...

133 is correct

Reply 14

2710

18

Original post by fliss1992

5 x 19 = 95
So we do 7 x 19 to get your answer

you said here do 5 x 19 = 95
then 7 x 19 to get your answer this equals 133

so what is it...

Sorry, for your original question. 133 is correcr

Posted from TSR Mobile

OP

Thanks

OP

I have another ratio question..

Split 500m in the ratio 1:4

& another

Split 4.8kg in the ratio 1:5

Do I work these out the same as the one before?

Original post by fliss1992

I have another ratio question..

Split 500m in the ratio 1:4

& another

Split 4.8kg in the ratio 1:5

Do I work these out the same as the one before?

First one:

Add the parts of the ratio

1 + 4 = 5 parts

Divide 500 m by 5 (the number of parts)

1 part is 100 m

If 1 part is 100 m how big is 4 parts?

Reply 18

fliss1992

OP

2

Original post by Mr M

First one:

Add the parts of the ratio

1 + 4 = 5 parts

Divide 500 m by 5 (the number of parts)

1 part is 100 m

If 1 part is 100 m how big is 4 parts?