## Sunday, December 6, 2009

### I stopped an Alien Invasion using Proportion (Late)

Red = Story
Purple = Math Question

Last Night an alien spaceship landed in my backyard and the little green man who steped out from the ship declared "If you cannot answer these three questions on proportion I will blow up your planet" to which I replyed "Why? I mean I get the whole alien blowing up up the earth but the whole pro-" "DO IT NOW!!!!!!!" he screamed "Ok, ok." I said.

1. Last night 30 cm of snow fell in 6 h. If it continues snowing at the same rate, how long will it take for 45 cm of snow to fall? Determine the answer two different ways.

First Way:
Well we know that 15+30=45 and that 15 is half of 30 so if we multiply 30 by 1.5 we get 45 so we multiply 6 h by 1.5 we get the answer which is 9 h.
Second Way:
This way is simpler in my opinionyou just divide both numbers by 2 and multiply it the results by 3 eg.
30 divided by 2 = 15 multiplied by 3 = 45
6 divided by 2 = 3 multiplied by 3 = 9
It would take 9 h for 45 cm of snow to fall.

2.The dosage of a certain medicine for a child is 2.5 ml for each 3 kg mass of the child. What is the dose, in millilitres, for a child with a mass of 16.5 kg?

To find the answer to this question we first need to know how many times 3 goes into 16.5
3 goes into 16.5 5.5 times
So to find out how much medicine this child needs we multiply the amount of medicine by the amount of times 3 goes into 16.5 which is 5.5
2.5 ml multiplied by 5.5 = 13.75
So the child that ways 16.5 kg would need 13.75 ml of medicine.

3.A small gear turns 18 times in the same time that a large gear turns 4 times. How many times will the large gear turn if the small gear turns 54 time? Draw a diagram to help set up a proportion and solve the problem.

Well we have to do this question essentially the same way as the last one by finding out how many times 18 goes into 54 which is 3 so we just multiply 4 by 3 to get the answer.
18 x 3 = 54
4 x 3 = 12
The large wheel would turn 12 times.

So after solving all three of the little green mans questions he said "Darn it, oh well I'll just blow it up next week, well goodbye." and I replied "Ok bye........Wait what?!?!?!!?"

1. Nice Job on Explaining your work Gordon! Yet such a late post...

2. good job..well explained

3. good job....