A bathtub can be filled by Tap X alone in x min and by Tap Y alone in y
min. If both taps are turned on at the same time, the bathtub can be
filled in z min.
A. If both taps are turned on at the same time, what fraction of the
bathtub is filled in one minute? Express your answer in x and y.
B. Find a formula connecting x, y and z.
C. Hence find the value of z when x = 20 and y = 12.
Neither do I understand the question nor do knew the steps to this
question. I would really appreciate if any of the readers could give me
to solution to the question or at least some hint on how I could solve
this question.
Chapter 3.4 , Simple Algebraic Fraction, More About Formulae
Secondary 2, Singapore
Originally posted by ---Max---:A bathtub can be filled by Tap X alone in x min and by Tap Y alone in y min. If both taps are turned on at the same time, the bathtub can be filled in z min.
A. If both taps are turned on at the same time, what fraction of the bathtub is filled in one minute? Express your answer in x and y.
B. Find a formula connecting x, y and z.
C. Hence find the value of z when x = 20 and y = 12.
Neither do I understand the question nor do knew the steps to this question. I would really appreciate if any of the readers could give me to solution to the question or at least some hint on how I could solve this question.
Chapter 3.4 , Simple Algebraic Fraction, More About Formulae
Secondary 2, Singapore
Originally posted by ---Max---:A bathtub can be filled by Tap X alone in x min and by Tap Y alone in y min. If both taps are turned on at the same time, the bathtub can be filled in z min.
A. If both taps are turned on at the same time, what fraction of the bathtub is filled in one minute? Express your answer in x and y.
B. Find a formula connecting x, y and z.
C. Hence find the value of z when x = 20 and y = 12.
Neither do I understand the question nor do knew the steps to this question. I would really appreciate if any of the readers could give me to solution to the question or at least some hint on how I could solve this question.
Chapter 3.4 , Simple Algebraic Fraction, More About Formulae
Secondary 2, Singapore
B. Z ( X + Y ) = XY
C. Z ( 20 + 12 ) = 20x12
Z = 7.5
Err why the fact is 1/x or 1/y? Why is it 1 divide by x?
I don't understand whould anyone enlighten me?
Originally posted by ---Max---:Err why the fact is 1/x or 1/y? Why is it 1 divide by x?
I don't understand whould anyone enlighten me?
tap x fill in x mins
if sharing the workload
x mins will become 1 / x bcos of the law of mathematics
tap y will share the workload thus become 1 /y
this is one of the uniqueness of algrebra
Originally posted by ---Max---:Err why the fact is 1/x or 1/y? Why is it 1 divide by x?
I don't understand whould anyone enlighten me?
fact: Tap X fills the tub in x minutes.
===> Now, imagine x is 5. putting in real numbers will help you grasp the problem better
fact: Tap X fills the tub in 5 minutes.
in 1 minute, it fills 1/5 of tub.
====> Follow so far? it's the same if you imagine x to be 10, 15, or 20..
so in 1 minute, it fills 1/x of tub
Okay... Thank you skywood but could anyone guide me step by step on how do I solve question b and c? How did the formula came out? I seriously don't understand.
b) you know that 1 min the tub is filled with 1/x + 1/y amount of water right?
So in z mins, the tank will be full so z X (1/x +1/y) = 1
multiply the equation by xy to remove denominator
zy + zx = xy
z (x+y) = xy
c) z (20 + 12) = 20 X 12
32z = 240
z = 7.5
assume volume = v.
time to fill volume with tap x = x mins, so spd = v/x
time to fill volume with tap y = y mins, so spd = v/y
also given in qn: time to fill volume with both taps = z mins
so... i have speed and assumed volume for taps x and y.
form equation with the above...
v / (v/x +v/y) = z
v will cancel each other out.. leaving the answer : x y = z ( y + x )
subt in values to find c. Ans is 7.5
i think.. wrong dun blame me:p
in one minute, Tap X fill 1/x of tub
in one minute, Tap Y fill 1/y of tub.
From question ==> if both tap turn on, tub will be filled in z minute.
======>I fill the tub in z minute using both tap, and get this equation
(1/x)*z + (1/y)*z = 1
=====> simplify
z(y +x)/xy = 1
z = xy/(x +y)
======> This is the simplest way i can explain it online. If you still can't grasp, i suggest you find your teacher.