x is directly proportional to y and x=300 when y =160 find the k the constand of variation
2006-08-05 08:05:04 · 10 answers · asked by investing1987 3 in Education & Reference ➔ Homework Help
k = 160/300
2006-08-05 08:09:35 · answer #1 · answered by Mellyssa N 2 · 0⤊ 0⤋
k=300/160
= 30/16
= 15/8
2006-08-05 15:12:12 · answer #2 · answered by flori 4 · 0⤊ 0⤋
x = ky
300 = k*160
so k = 300/160 = 1.875
listen about your previous question about the tank and faucets, here is the answer:
You can do this by making two equations and then solve.
Imagine the following:
The first faucet will fill portions during the 1.5 hours, so imagine that at a specific time it filled x portions.
The second faucet will fill also portions during the 3 hours, so at a specific time it filled y portions.
so we conclude that the first equation is :
the portion x + the portion y = 1, which is a full tank.
Now, the portion filled by the first faucet*the time required to fill it, should equal the portion filled by the second faucet*the time required to fill.
so x*1.5 = y*3
1.5 x = 3y
divide by 1.5
x = 2y, the second equation
so by substitution:
x+y = 1
(2y) +y = 1
3y = 1
y = 1/3
so the portion y is 1/3 of the tank.
whole tank (1) : 3 hours
(1/3) of tank : ? hours
so ? = (1/3)*3/1 = 3/3 = 1 hour to fill the tank.
you can make sure of the answer by doing the last procedure to x:
first x+ 1/3 = 1
so x= 2/3
whole tank (1) : 1.5 hours
(2/3) of tank : ? hours
so ? = (2/3)*1.5 = 1 hour
2006-08-05 15:15:41 · answer #3 · answered by Turkleton 3 · 0⤊ 0⤋
...how old are you?
i'm thirteen and i just passed that class. ;o
let me think. directly proportional would be y/x = k, or y = kx (divide it by x to get the first one, they're the same).
so the answer is 160/k = 300. this equals 160 = 300k.
that's 160/300, or 16/30. this further simplifies to 8/15. good luck!
2006-08-05 15:14:08 · answer #4 · answered by kae 4 · 0⤊ 0⤋
x is directly proportional to y translates to
x = ky, where k is the constant of proportionality
Substitute in your values for x and y and solve for k.
300 = k(160)
Divide both sides by 160
300/160 = k
Reduce
k = 15/8
2006-08-05 15:33:18 · answer #5 · answered by MsMath 7 · 0⤊ 0⤋
In direct proportion,
x = k*y
If x=300 and y =160
300 = k*160
k = 300/160
k = 15/8
[speech omitted..]
2006-08-05 22:59:33 · answer #6 · answered by Anonymous · 0⤊ 0⤋
totally hope there is some math nerd on here for you.
wish I could have done that with some of my homework!
2006-08-05 15:09:45 · answer #7 · answered by sofun 4 · 0⤊ 0⤋
Dude you're like putting all your homwework questions on this thing. Not cool.
2006-08-05 15:09:06 · answer #8 · answered by pete 3 · 0⤊ 0⤋
You really need to do ur hw urself or get a tutor!
2006-08-05 15:09:00 · answer #9 · answered by Simply Me 3 · 0⤊ 0⤋
The answer is: "The treaty of Versailles"
2006-08-05 15:09:57 · answer #10 · answered by Anonymous · 0⤊ 0⤋