Algebra Tutorial - 9 - Solving Word Problems with Equations

[kellog]

its probably just a preference though. the porportons is the same thing. just fractions used to drive me nuts but your example does help me understand alittle better to solve things that way

[Insune]

I love all of these videos, thanks for the upload!

[kellog]

i dont know how to put that in a equation but I naturally know that I can half 150 which is 75. then half of 5 is 2.5. so I subtract that from 75 and which is 72.5 and I can add 2.5 to 75 which is 77.5 to create the 5 unit difference . 77.5 - 72.5 is 5. since we know the width is greater by 5 your width is 77.5 and your length is 72.5

[TheBlackMambaGR]

l=w + 5m(1)
p=150m(2)
p= 2*l +2*w(3)
combining these 3 equations you get:
2*(w+5) + 2*w=150m
=>2w +10 +2w=150m
=>4w+10=150m
=>4w=140m
=>w=35
So we have found the width. Now, in order to find the length, we come back to equation (1)=>l=w + 5m=> l=35 + 5=> l=40
There you go :)

[alevzykzlvylakznav]

I know this video is very old but I still want to point out that.
I really like how you go "aahh" "aahh" it encourages me to (re) watch all the videos.

[XTREMEX]

I do 4/5c=64. Divide both side by 4 so 1/5c=16. 4/5c=64 + 1/5c=16 is 80. Way easier

[kellog]

actually just figured out how to write it out myself in equation
150= L+L+5 cancle the 5 to get -5
150-5= 145
we know anything plus itself is the same as itsef times to. ex 7x2=14 7+7=14
so 145/2 = 72.5=L
L+5=W

[kellog]

you didnt have to check your last question like that. since you know 4/5 is 80% you could have just multiplied 80 times .80 and you should get 64as 4/5 since 80 is the whole class. 100%.

[angus]

For that last question you could have just done 64/0.8

[loulouvince]

The sum of twice a number and 211583. Find the number.
WHAT?!

[osibarragan]

are u sopose to do this in 5th grade because ia doing this in 5th but i think its hard

[kieranisland]

this seems like alot of effort when you could subtract 21 and devide the remainder by 2.

[sonypsp]

I have to solve (x-24) if I have 24 coins and I have to count the coins within 24. Witch totals $4.50 I counted 10 Dimes and 14 Quarters. Would the answer be 4? If not than I did something wrong.

[TheBlackMambaGR]

why is that? I think it's very clear...
l = length
p = perimeter
w = width
which part do you not understand?

[kellog]

lol i got the the question backwards but yea you should pick up how to solve it. my main problem in math is that I misread alot lol your width is 72.5 your length is 77.5

[biancaa]

So twice a number is 2 times a number, no kidding Sherlock?

[kellog]

thats really unclear man i dont think anyone is gunna be able to read that lol

[delljack]

i did not sub to this person y is this in my sub box