2 cups self raising flour, sifted (250g at 0.32c per gram)
2 large eggs, separated (40 cents each)
2 cups milk (500ml at 0.25c per ml)
2 tsp sugar (8 grams at 0.024c per gram)
50g butter, melted plus extra butter or oil for cooking (at 0.88c per gram)
How much do you think it costs to make pancakes at home? How much do you pay at a cafe or McDonalds? When restaurant owners and chefs calculate the cost of their menu they need to take into account the cost of ingredients as well as staff costs, overheads (rent, power, telephone, gas etc) and also make a profit.
Scratch is simple-to-use software, that allows users to create animations using drag-and-drop commands. I hope to use this free program, pre-installed on our government school laptops, as part of our geometry learning this term.
Scratch uses the Cartesian Co-ordinate system to locate ‘sprites’ on a ‘stage’.The screen is a 480 x 360 rectangle, such that: the X position can range from 240 to -240, where 240 is the rightmost a sprite can be and -240 is the leftmost, and the Y position can range from 180 to -180, where 180 is the highest it can be and -180 is the lowest it can be. The centre of the screen, or ‘origin’, is known as (x=0, y=0) or (0,0).
The following links are some examples of what can be achieved with Scratch.
Pythagoras was a famous mathematician who lived about 2500 years ago. He is credited with being the first person to prove that in any right-angled triangle there is a special relationship between the squares of the three sides. The theorem has an important role to play in everyday life because right-angled triangles occur in construction, navigation, planning, design and packaging. Pythagoras’ theorem is one of the great geometrical theorems.
Cup cake recipe (makes 12 small or 6 large cup cakes)
1/4 cup butter (60 grams)
1/4 cup caster sugar (60 grams)
3 drops vanilla essence
3 tablespoons milk (1 tbsp = 20 ml)
3/4 cup S.R. flour (115g)
Method: Set the oven at 200 degrees Celcius. Cream the butter and sugar until light and fluffy. Add essence and egg, mixing well. Add flour and milk alternately, one-third at a time. Stir gently and thoroughly. Place mixture in paper patty pans, two-thirds filling each one. Bake at 200 degrees for 1/5 to 1/4 of an hour. Cool in pans, then decorate each cake with icing.
1. Draw up a table and write out the ingredients required for 12 large and 24 large cupcakes.
2. If you want to have equal numbers decorated the same, what different numbers can you use? (What are the factor pairs of 24?)
3. How many minutes is 1/5 of an hour? How many minutes is 1/4 of an hour?
4. If (20ml x 3) of milk is required for 6 large cupcakes, how much of a cup is required for 12 and 24 cupcakes?
5. Calculate the cost of the ingredients for 24 large cupcakes using the Coles or Woolworths online shopping website.
This is a picture of a mechanical calculator, common in Europe in the 1960’s. Imagine using one of these in school! We are lucky now to have very cheap and efficient electronic calculators that can do quite sophisticated operations. However, it is still important to have automatic recall of number facts – like when collecting change at a shop, calculating wages and saving for something special.
This week we will be practicing basic operations – multiplication tables up to 12, indices, order of operations (BODMAS) and short division. In Year 8 we will be doing operations with negative numbers. There are several FREE apps that you can access on mobile devices to practise basic operations:
***Wishball (place value, adding and subtracting)
***Motion Maths Hungry Fish (addition)
***Motion Maths Wings (multiplication)
King of Maths
Times Tables Quiz!
IXL Maths Practice
***I have tried and recommend these ones, but there are lots more available. Choose one, tell me about it and let me know what you think in the comments below. Please continue to work on your Mathletics activities and Mathsmate worksheets (due Friday).