Mathematics, 29.07.2019 01:30, naimareiad

Jean and mark are going to fill a pool with 2 different sized hoses. jean can fill the pool in 8 hours, while mark can complete it in 12 hours. their supervisor thinks that the job will take 10 hours to complete if they work together. explain each step in solving the equation, and determine if the supervisor is correct or not.

Answers: 1

Show answers

Answers

answered: 2016gbryant

Calculate Jean's rate

Jean takes 8 hours to fill the pool.
So in 1 hour, she can fill 1/8 of the pool

Calculate Mark's rate

Mark takes 12 hours to fill the pool.
So in 1 hour, he can fill 1/12 of the pool.

Calculate their rate if they work together

Jean = 1/8
Mark = 1/12
1/8 + 1/12 = 3/24 + 2/24 = 5/24
They will fill 5/24 of the pool in 1 hour

Find number of hours needed to fill up the pool

I hour = 5/24 of the pool
1 ÷ 5/24 hour = 5/24 ÷ 5/24 of the pool
24/5 hour = Whole pool

Whole pool = 24/5 hours
Whole pool = 4 4/5 hours or 4.8 hours

Ans: The supervisor is not correct, it will take only 4.8 hours if both of them work together.

answered: Guest

f is the midpoint of

answered: Guest

when functions are first introduced, you will probably have some simplistic "functions" and relations to deal with, usually being just sets of points. these won't be terribly useful or interesting functions and relations, but your text wants you to get the idea of what the domain and range of a function are. small sets of points are generally the simplest sorts of relations, so your book starts with those.

step-by-step explanation:

state the domain and range of the following relation. is the relation a function?

{(2, –3), (4, 6), (3, –1), (6, 6), (2, 3)}

the above list of points, being a relationship between certain x's and certain y's, is a relation. the domain is all the x-values, and the range is all the y-values. to give the domain and the range, i just list the values without duplication:

domain: {2, 3, 4, 6}

range: {–3, –1, 3, 6}

(it is customary to list these values in numerical order, but it is not required. sets are called "unordered lists", so you can list the numbers in any order you feel like. just don't duplicate: technically, repetitions are okay in sets, but most instructors would count off for this.)

while the given set does indeed represent a relation (because x's and y's are being related to each other), the set they gave me contains two points with the same x-value: (2, –3) and (2, 3). since x = 2 gives me two possible destinations (that is, two possible y-values), then this relation is not a function.

note that all i had to do to check whether the relation was a function was to look for duplicate x-values. if you find any duplicate x-values, then the different y-values mean that you do not have a function. remember: for a relation to be a function, each x-value has to go to one, and only one, y-value.

state the domain and range of the following relation. is the relation a function?

{(–3, 5), (–2, 5), (–1, 5), (0, 5), (1, 5), (2, 5)}

i'll just list the x-values for the domain and the y-values for the range: