I don't understand this easy MATHS Q!!

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HumbleBee_x
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Report Thread starter 8 months ago
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This is from my bio paper:

A student investigated the glucose concentration in five different drinks.
His results are shown below.

*the graph shows that drink F's concentration of glucose/g dm^-3 is 5*

Using the data, calculate how many grams of glucose would be in 220 cm3 of drink F.

The answer is: 1.1 grams

Idk what i'm doing wrong I did 220 x 5 which is 1100 , but I don't get how you work with units to get it to grams

Help would be appreciated
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Caiyren
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there are 1000 cm^3 in 1 dm^3

so 220cm^3 would be 0.22dm^3, then you would do 5 g dm^-3 x 0.22 dm^3

that would give you 1.1 grams as dm^3 cancel out.

this is what i did. not sure if its right.

sorry this is abit rushed hope it helps

i divided the 220 by 1000 to get it from cm^3 to dm^3
Last edited by Caiyren; 8 months ago
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Muttley79
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(Original post by HumbleBee_x)
This is from my bio paper:

A student investigated the glucose concentration in five different drinks.
His results are shown below.

*the graph shows that drink F's concentration of glucose/g dm^-3 is 5*

Using the data, calculate how many grams of glucose would be in 220 cm3 of drink F.

The answer is: 1.1 grams

Idk what i'm doing wrong I did 220 x 5 which is 1100 , but I don't get how you work with units to get it to grams

Help would be appreciated
5g is per dm^3 - you have been given a volume in cm^3 .... you need to convert your volume to the correct units.
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HumbleBee_x
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thankyou so much I understand
do the dm^3 cancel out because one is -3 and the other is 3?
(Original post by Caiyren)
there are 1000 cm^3 in 1 dm^3

so 220cm^3 would be 0.22dm^3, then you would do 5 g dm^-3 x 0.22 dm^3

that would give you 1.1 grams as dm^3 cancel out.

this is what i did. not sure if its right.

sorry this is abit rushed hope it helps

i divided the 220 by 1000 to get it from cm^3 to dm^3
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Caiyren
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yes. youre right, the dm^3 and dm^-3 are being times together so cancel out.
(Original post by HumbleBee_x)
thankyou so much I understand
do the dm^3 cancel out because one is -3 and the other is 3?
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