## Welcome to H3 Maths

Blog Support for Growing Mathematicians

## Posts tagged with ratios

May2

Taking a person, when squatting, to be approx. a meter in diameter, we end up with the following ‘radical ratios’: 1. The size of a human cell to that person is the same ratio as a person’s size to Rhode Island 2. The size of a virus to a person is the same ratio as […]

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### The Mathematics of Scale

April30

Hey – do you enjoy making model cars, boats, planes, dolls houses, or even F1 racing cars? Modelling is great fun and most model kits come with a scale on the front of the box, such as 1:50 or 1:100. I recently saw a modelling kit of the Starship Enterprise, which had a scale or […]

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### Ratios are really useful

March1

We are on to Chapter 2, titled Ratios. The pyramid at Giza has some amazing mathematical properties and was probably constructed to scale using ratios from a model or sketch (I showed how this works in class). Last period we learned how to simplify ratios and also how to use the cool ratio method that […]

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#### Post Support

NCEA Level 2 Algebra Problem. Using the information given, the shaded area = 9, that is:
y(y-8) = 9 –> y.y – 8y – 9 =0
–> (y-9)(y+1) = 0, therefore y = 9 (can’t have a distance of – 1 for the other solution for y)
Using the top and bottom of the rectangle,
x = (y-8)(y+2) = (9-8)(9+2) = 11
but, the left side = (x-4) = 11-4 = 7, but rhs = y+? = 9+?, which is greater than the value of the opp. side??
[I think that the left had side was a mistake and should have read (x+4)?]