Help please with 2 equations...

[piggynose]

1. Jacky joins a video club.
She has to pay a membership fee and then 2 quid for each video she rents.
a) write this as a formula in words.
b) work out the total amount Jacky will pay if the memebership is 5 quid and she rents 15 videos.( is this 15 x 2 +5= 35 quid?)

2. The instructions for cooking a turkey are " allow 45 minutes for each kg the turkey weighs, then add another 30 mins"
a) copy and complete this formula in words:
time to cook a turkey =
b) how many minutes will it take to cook a turkey weighing 10 kg?

[scotman]

assume P = payment; F = membership fee; N = number of videos rented

then

P = F + 2xN

[ChuckFickens]

and 2)
(weight times 45) + 30

and

480min

(is this primary school maths homework)

[piggynose]

you would´nt beleive it, but i was top of my class in maths about 40 years go, you ask what happened? looks like i´ve totally forgotten everything.
I´m trying to review maths by looking at a modern book. its embarrassing.
i even thought the turkey question was 10 x 45+30 = 750 mins, until i discovered a new formula, BIDMAS. now things are slightly clearer.

[ChuckFickens]

That's why the brackets are important, scotmans answer should really be

P=F+(2*N)

With the brackets showing you work the part out inside them first, in your example the correct answer to the first part is

5+(2*15)=35

without the brackets somebody might work the same sum out as

(5+2)*15=105

(either that or use Reverse Polish Notation, which I use on the calculator I use are work sometimes)

[The Builder]

I think that should be BODMAS, Piggers................ the O is "of"

[ChuckFickens]

Either work (although I think BIDMAS makes more sense)

http://maths-wiki.wikispaces.com/Bidmas

[factor-fiction]

It's taught as BIDMAS (I is Indices), TheBuilder.
Used to be BODMAS in our dschooldays- I think the O stood fro Order or to the power Of

[The Builder]

(hangs head in shame) .................... now I feel old (er)

[THECORBYLOON]

Chuck, brackets aren't needed. The video formula can be written as C = 2V + 5 where C is the total cost and V is the number of videos. Using the BODMAS rule gives the correct answer.

[Prudie]

me too the builder, I learnt it as BODMAS (with the O as of). BIDMAS is another ridiculous output from some trendy educational group who have to change everything IMO.

[The Builder]

Ahh, Pruders .............. in my job, I pride myself on being bi-lingual. I confuse people no end with measurements of "one metre, three and a half inches" all the time :o)

[piggynose]

thanx folks.
no thanx to modern maths though. if its not broken why fix it?

[factor-fiction]

I don't understand what your comment means, piggynose. Changing the term BODMAS to BIDMAS makes absolutely no difference to how we get the answer to these problems.
I don't think we even need to think about BIDMAS/BODMAs here.
For example in question 2 if every kg needs 45 minutes then you simply multiply the weight in kg (10) by 45 to give 450 minutes. Then add on another 30 minutes. That gives you 480 minutes (6 hours)

[factor-fiction]

^ oops- 8 hours!

[piggynose]

factor 30, i´m just showing my frustration as not getting it. It will need more study from my part. Surely i havent become thick overnight.

[factor-fiction]

I suggest you talk yourself through each question.
-45 minutes for each kilogram.
-You have 10 kilograms so that's 450 minutes.
-Then, as the rule says, you then add another 30 minutes. That makes it 480 minutes.

On

[Old_Geezer]

40 years ago, wow that was a long (over)night :-)

[piggynose]

lol OG

[nescio]

just to confuse things further, I learnt the rule as BEDMAS, where the E stands for exponentiation