7/30/2019 Unit 8 Math Project Revised

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TODAYS WASTAGE IS

TOMORROW'S

SHORTAGEWhat does it take a family of four touse 300 KwH/month? For my yearlongproject, I worked with my family inorder to reduce our electricityconsumption. Although my familys

electricity usage isnt that bad, I stillfelt that there was room forimprovement. So I decided to take it asa challenge and reduce my familysusage. I started of this project bymaking a clear and organized plan andthen implementing it in our daily life.

The first step we took towardsconserving electricity was switchingoff the lights and air-cons when not inuse! My plan also included thefollowing steps: setting the air-cons to23 degree celsius, making use ofdaylight in the morning, turning on thewashing machines only with full loads,turning off all the electronicappliances when not in use, chargingthe electronics (iphones, ipads, laptopsetc.) in the morning instead ofcharging them overnight andovercharging them. Although we cameup with this plan and we agreed tofollow the plan, everything didnt go asper the plan because we kept forgettingabout it. So then I came up with anidea, and we decided to put stickynotes all around the house, specially,beside the switchboards as a reminder.

That idea really helped my family tokeep up with the plan and implementit.

My family has been very

supportive and cooperative with

helping me. My familys efforts

can be seen in the results as we

have come down from 575 KwH in

August to 485 KwH in March.

There were a few ups and downs

in the middle though. For

example, in November and

February my KwH went up

because we werent following our

plan due to many other

distractions like in February I had

guests so there were more people

in the house, which resulted in

using more electricity. As you can

see in the data, December is the

month when I actually stayed on

top of the plan and made sure that

everyone followed it and so my

efforts showed of in that months

bill. I hope that we continue this

plan and make consistent efforts

to have a sustainable living.

Lookin at the Results

May 7th, 2013 SNEKHA SELVAKUMAR

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7/30/2019 Unit 8 Math Project Revised

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By Snekha

The first step towards making a

prediction is drawing a fitted line in

the graph with my monthly data. The

efforts of my family have proven to

have paid off as the fitted line on the

graph has a negative slope which

means that my electricity usage has

been decreasing. The next step is to

find the equation of this fitted line. To

do this, I chose two points (1, 539)

and (7, 485). In order to find the

equation of the line, I need to use the

formula y=mx+b. So lets first start by

finding the slope of the line by using

this formula:

So now, just substitute and solve it:

Now I know that the slope of my fitted

line is -9. So far this is what my

equation looked like: y = -9x+b. Next, I

have to determine my y-intercept. To

do this, I will have to substitute any

one of the coordinates with x and y.

In my case, I chose to substitute the

ordered pair (1, 539). Heres what it

will look like after substitution:

Now we solve this

equation to find out y-intercept(b).

Following are the steps of how I found

b using the formula above:

Therefore, the equation of my fitted

line is y= -9x + 548. Now I will use this

equation to make a prediction about

how many months it will take my

family to bring my monthly electricity

usage to 300 KwH.

LINEAR RELATIONSHIPS

AND TRENDS

Considering that my fitted line goes downhill and is a example of

linear decay, this matches with the trends that my family is working

towards to make a positive difference. There is a clear and strong

relationship between the line and the trends. The more electricity

we conserve each month the steeper the slope will be. There is

also a clear connection between the efforts my family has put in

this the action and the line because when we put in more effort

and make sure everything goes right, the KwH decreases however

sometimes when we become careless and forget about our plans,

then again our usage goes up drastically. This can be clearly seen in

my graph and my table.

MAKING A PREDICTION!Now that I have my equation, I just need to substitute and solve to find

the no. of months it will take my family to bring down my electricity

usage to 300 KwH per month. As y represents the amount of KwH in

the equation, we have to substitute 300 for y and then solve for x. So

this what the substitution and the solving should look like:

In conclusion, it will take my family approximately 28

months to bring our electricity usage down to 300 KwH

if we continue reducing our usage at this rate!

Finding the Equation ofm Fitted Line!