Standard Math Q+A Thread

[jamonwindeyer]

here is the question from above for the marshmallow one
sorry pls explain further?

Sure! So the dimensions of that big prism of marshmallows can be found by clever adding of the dimensions, it is 20cm by 15cm by 6cm, see if you can spot how they line up. The volume is:



But that's counting the gaps as well - The volume of the marshmallows is just the 24 times the volume of the cylinder. Remember the radius is half the diameter:



Multiply by 24 to get the total marshmallow volume:



And the difference between the two is your answer - The gaps where the chocolate will go...

Edit: Almost. Except the chocolate only goes into half the gaps I am speaking about. So to get the final answer, we halve that final answer

[harry77]

but then how would I find the daily growth rate of the pig?
Like is there a formula or something coz the answers literally just give me the answer

hello
i need help with this too? pls
thanks

[jamonwindeyer]

but then how would I find the daily growth rate of the pig?
Like is there a formula or something coz the answers literally just give me the answer

Could you upload the question specifically?

and maybe their answer too? Sorry just want to make sure I interpret it correctly

[harry77]

here u r

[jamonwindeyer]

here u r

Cool! So you can tell from the formula they use, the 1.1 is the giveaway, but you can also tell by picking any two days and comparing. Say Day 1 and Day 2:



Then we just divide Day 2 by Day 1 and we get:



So the Day 2 mass is 110% of the Day 1 mass, a growth of 10%! You could do this with any two days and it would work - Or you could spot it in the formula they use

[MisterNeo]

hello
i need help with this too? pls
thanks

[Rainbowhippocampus]

Hey there, question do we have to remember the different dosage formulas for children and adults?
Thank you

[jamonwindeyer]

Hey there, question do we have to remember the different dosage formulas for children and adults?
Thank you

Nope, they will be given to you!

[Rainbowhippocampus]

AWESOME THANK YOU

[[MA165]]

Hey!
i find probability really confusing in this course... especially trying to work out what technique as such to apply and when...
so... is nPr applied to unordered data as such... eg) something that can be used more than once.... and nCr used when things can only be used once... eg) selecting people for a committee?
sorry... that possibly made no sense??!

[jamonwindeyer]

Hey!
i find probability really confusing in this course... especially trying to work out what technique as such to apply and when...
so... is nPr applied to unordered data as such... eg) something that can be used more than once.... and nCr used when things can only be used once... eg) selecting people for a committee?
sorry... that possibly made no sense??!

Welcome to the forums! I instead like to think of it as:

- nPr is when order does mattter
- nCr is when order doesn't matter

For example, if there are 10 people and I'm selecting 5 for a committee, then that can happen in 10C5 ways. But if I'm, say, voting for 5 of them in order of preference (order matters), it would be 10P5 ways.

In general, you can always choose the things only once, but it's whether you care about the order when you are done or not that determines which you use

[[MA165]]

Welcome to the forums! I instead like to think of it as:

- nPr is when order does mattter
- nCr is when order doesn't matter

For example, if there are 10 people and I'm selecting 5 for a committee, then that can happen in 10C5 ways. But if I'm, say, voting for 5 of them in order of preference (order matters), it would be 10P5 ways.

In general, you can always choose the things only once, but it's whether you care about the order when you are done or not that determines which you use

Ohh!! i get it!! Thankyou v much!!!!

[emilybrooks99]

Can someone help me out with this question and explain it thoroughly cause standard deviation is where I always go wrong. Thanks

[jamonwindeyer]

Can someone help me out with this question and explain it thoroughly cause standard deviation is where I always go wrong. Thanks
(Image removed from quote.)

Hey! So with a mean of 3.1kg, we need to look at everything with respect to the standard deviation of 0.35kg. Notice that 2.75kg is one standard deviation below the mean and 4.15kg is three standard deviations above the mean.

This diagram does the best job showing how much is in each of those standard deviations:



We want from -1 to 3, from one standard deviation below to three above. Add those percentages up:



And then find how many babies this is:

[[MA165]]

Hey... is anyone able to help me out on how to go about this question?
it refers to the question before which just states what is found in a deck of 52 cards... 4 suits,  each suit has 9 numbers, one ace, and a jack, queen and king...
MANY THANKS!