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    I'm terrible at maths and so I can't get my head around this calculation.

    Dilute 5 uL of blood 1:2000 with solution Y.

    All I can come up with is:

    1:2000

    .:. 5uL : 10,000uL

    .:. add 10mL of solution Y?

    But apparently we're meant to do serial dilutions which I've never understood.

    I would really appreciate help with this topic.

    Edit: I've had a quick Google and attempted it so that you guys know I'm not trying to get someone to do my homework for me lol. This is what I have but no idea if it's correct

    - Test tube 1: Add 19uL solution Y and 1uL blood to produce 1:20 dilution
    - Test tube 2: Take 1uL from test tube 1 and add to 19uL solution Y to produce 1:200 dilution
    - Test tube 3: Take 1uL from test tube 1 and add to 19uL solution Y to produce 1:2000 dilution

    Is this correct?

    Thank you.
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    Yes, this is correct. Serial dilutions work in powers of 10, to keep the maths simple.
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    (Original post by Sparkliest)
    I'm terrible at maths and so I can't get my head around this calculation.

    Dilute 5 uL of blood 1:2000 with solution Y.

    All I can come up with is:

    1:2000

    .:. 5uL : 10,000uL

    .:. add 10mL of solution Y?

    But apparently we're meant to do serial dilutions which I've never understood.

    I would really appreciate help with this topic.

    Edit: I've had a quick Google and attempted it so that you guys know I'm not trying to get someone to do my homework for me lol. This is what I have but no idea if it's correct

    - Test tube 1: Add 19uL solution Y and 1uL blood to produce 1:20 dilution
    - Test tube 2: Take 1uL from test tube 1 and add to 19uL solution Y to produce 1:200 dilution
    - Test tube 3: Take 1uL from test tube 1 and add to 19uL solution Y to produce 1:2000 dilution

    Is this correct?

    Thank you.
    Your first step is correct to reach a 1/20 dilution. But then both subsequent steps are diluting 20x so you reach 1/400 and then 1/8000 respectively. You need to dilute by 20x once and 10x twice. (Or whatever other numbers you choose... as long as the product is 2000).
 
 
 
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