S3 Maths Scribe-post Blog

In todays lesson, we continued direct proporion

Example:

6 bags of bowling balls weigh 15 kg. How many bowling balls would weigh 35 kg?

We find out how much one bag weighs by a simple division: 6/15=0.4

We lay this out in a table: Weight (kg) Bowling Bags

15 6

1 6/15=0.4

35 35*0.4=14

We then moved on to Recipes

Example: A Sponge Cake Recipe for 6 people

6 medium eggs

340g self raising flour

340g butter

340g caster sugar

How much ingredients would be needed for 9 people?

We can work this out by doing the following:

Eggs: 6/6*9=9g

Self raising flour: 340/6*9=510g

Butter 340/6*9=510g

Caster sugar: 340/6*9=510g

All you need to do is divide the amount of ingredients but the amount of people it serves, then you times it by the number of people you would like to change it too!

I chose Katie as the next person

In thursdays lesson we discussed direct proportion!!

Direct proportion is when you start off with the price or weight of the amount of some thing:

Price/Lollipop

10p / 1

we then coould be asked wat the price of 5 lollipops would be???
So if one lollipop is 10p then if we use direct proportion we should relise that the other 4 lollipiops would be 10p so add the amount together and u work ure way up to find out that h lollopops would be 50p.

price/lollipops

10p / 1

50p/ 5

The way for working this out is by dividing the weight cost or height ect.. by the amount of product you have so you find out the amount of one. then you times it by the requested amount of product to get your answer!!

it may sound confusing but its very simple…………

try some of these…

1a)
bricks/weight

5 25g

find out the amount to two bricks?

2a) sweets/cost

2 30

find the cost of 4 sweets??

i have chosen hollie for the next blog

direct proportion is about having a equal proportion

For example:I sell some choclate. 5 pieces for a £1. so  by finding out how much a piece is by dividing 100 by five which equals 0.20p.If i sold 10 pieces it should be £2 pounds because I am selling double the amount of choclate.

www.bbc.co.uk/choosls/gcsebitesize/maths/algebrah/proportionrev2.shtml     

I choose Dan coll

btw i choose connor

what is a highest common factor (h.c.f )? Well a highest common factor is a number that goes into two sets of numbers a single number of times. Example - 8 and 12 the highest common factor would be 4 because it goes into them an exact number of times. Factorizing is when u get a sum like 4x+12= well this is what u would do 4(x+3) because when u brake the brackets then you will get 4x+12

website

hello !

In this leason we learnt about electricity bills and how to find out how much we would have to pay.

EXAMPLE:

Apr-04 Reading- 34436 units  - previous

Jul-04 Reading- 35231 - present

We found out that we had to take away the pervious from the present -

 35231 - 34436 = 795

The first 1100 units where 25 pence each so we times the amount of units by the cost -

25 x 795 = 19875

So the cost of the bill was 19875 pence or £198.75p

We also found out why it cost more for the first 1100 units and after it costs less. This is because the men who work for the companies need 2 be payed and it the extra cost is to pay for that and it becomes cheaper after that.

We also learned about Standing charge. This is when there is a set charge for for the bill for just having it connected to this company. This means that normally the first 1100 units would cost 25 p each and after that it would cost 11p for a unit but now it means that that all the units will cost 11p plus the 100 pounds to be connected. If you are using alot of electiricty this will save you money but if you are an elder member they dont advise it because they dont tend to use that much electricity.

Today we found out about highest Common Factors

 Example:

The factors of 12 are 1, 2, 3, 4, 6 and 12.

and the factors of 8 are 1, 2, 4, and 8 which means the common factors of 12 and 8 are 1, 2 and 4.

So the Highest Common Factor of 12 and 8 is 4.

because if you have a look at the common factors the biggest number is 4.

Can you find the highest common factor of:

24 and 30?

Todays lesson was all about Prime Numbers. The main aims were to

• Find out all the prime numbers up to 100

and to….

• Find out how to find all the prime factors upto 100

First of all we looked at a “Sieve of Eratosthenes” which ended up looking something along the lines of this;

The numbers that are in black are all prime numbers up to 100.

Later on in the lesson Mr Jones then taught us an easy little method;

24
       8  x   3
     4 x  2
   2 x 2

The 2,2,2,3 are all the prime numbers. They also add up times to make 24 so these are the prime factors of 24.