Simon makes a model of a boat, using a scale of 1 : 30 If the model has a height of 40 cm, find the height of the real boat.

Give your answer in metres.

12 metres

Step-by-step explanation:

The scale factor used for the model is 1 : 30.

This means that for any 1cm on the model, the real boat would be 30 cm.

If the height is 40 cm on the model, the real boat will be 30 times that:

= 40 * 30

= 1,200 cm

A metre is equivalent to 100cm.

1,200 cm would therefore be:

= 1,200/100

= 12 metres

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

b. y = 4x - 2

step-by-step explanation:

to find a parallel equation to an equation, make sure both equations have the same slope but different y-intercepts.

y = 4x + 1

4 = slope

1 = y-intercept

y = 4x - 2

4 = slope

-2 = y-intercept

they both have the same slope but different y-intercepts, so, b. is the correct answer.

and to check your work, you can graph both equations. : )