Question

Composition of Functions Word Problem Practice Worksheet: I finished the whole worksheet, but I am not for sure if it has the correct answer on, so I need help making sure that it's the correct answer. **Medal and fan will be rewarded for all help!!!!!!!!!!**

Answer 1

sorry I don't have the program to open docx files

Answer 2

if you can convert it, then it might work

Answer 3

How can I convert

Answer 4

there should be a feature when you save it

Answer 5

like "save as blah blah blah"

Answer 6

that's where you change the format

Answer 7

can you open pdf files

Answer 8

yes

Answer 9

1a and 1b are correct

1c is not correct, it's close though

Answer 10

(d o t)(x) is the same as d(t(x))

Answer 11

so you start with d(x)

and replace x with t(x)

Answer 12

d(x) = 0.7x

d(t(x)) = 0.7(1.0575x)

d(t(x)) = 0.74025x

(d o t)(x) = 0.74025x

so this function helps you compute both the discount and the tax at the same time (you do the tax first, then apply the discount)

Answer 13

(t o d)(x) is the same idea, just swap the roles of d(x) and t(x)

Answer 14

oh okay it's different answer correct

Answer 15

no you should get the same either way

Answer 16

same answer

Answer 17

1f is correct

1g is close, but you need to round to the nearest penny

Answer 18

oh and 1e, it doesn't matter which one you use since in this particular case (d o t)(x) = (t o d)(x)

Answer 19

$135.09 is my answer for g

Answer 20

correct

Answer 21

was 1d. wrong for the explanation?

Answer 22

I don't know what you mean by 'add it up'

Answer 23

look back at my steps at how I got d(t(x))

Answer 24

I don't know either, but on that part do you do the discount first, and then apply the tax

Answer 25

d is discount first, then apply the tax, yes

Answer 26

c is tax first, then discount

Answer 27

so is #1 checked out okay

Answer 28

yeah

Answer 29

#2 is there anything wrong with it

Answer 30

instead of 397 for 2c, I'm getting 397.44 roughly

so don't forget that decimal part

Answer 31

other than that, 2 looks good

Answer 32

do I have to add that, I kind of rounded it

Answer 33

I'd keep the decimal portion

maybe round to 2 or 3 decimal places

Answer 34

#3?

Answer 35

any problems besides 3b. which I am not for sure about

Answer 36

how are you getting 1986 ?

Answer 37

oh nvm

Answer 38

you used the function with 2000 as the input

Answer 39

for month 3, I'm getting 1,957.239

that rounds to 1,957.24

you need to round to the nearest penny when you write your answers (but don't round when using those figures in the calculator)

Answer 40

is month 1 and 2 okay for chart

Answer 41

yeah

Answer 42

month 4 & 5

Answer 43

those look good too

Answer 44

did I need to round for month 3

Answer 45

yes you should round to the nearest penny

Answer 46

What's b for #3?

Answer 47

one sec

Answer 48

any luck with solution

Answer 49

I'm trying to find how to solve recurrence relations, but I'm not having any luck

I'll look for how to find remaining balance, one sec

Answer 50

well I found this at least

http://www.calcxml.com/calculators/pay-off-loan

Answer 51

can you tell me how #4 is and see if it needs to be fixed then worry about the recurrence relations?

Answer 52

the annual rate is (1.8%)*(12 months) = 21.6%

Answer 53

for #4, I'd simplify the answer you got for c

Answer 54

@jim_thompson5910 I said x/12 over 2.54

Answer 55

I'd simplify \[\Large \frac{x}{12} \div 2.54\]

Answer 56

what do you get when you do so

Answer 57

you confused me, I don't think I am suppose to get and true answer for this like 5 for example

Answer 58

x/12 divided by 2.54 is the function to use

Answer 59

you can simplify though

Answer 60

\[\Large \frac{x}{12} \div 2.54 = \frac{x}{12} * \frac{1}{2.54} = ??\]

Answer 61

@jim_thompson5910 4.72 I guess

Answer 62

no just multiply straight across

Answer 63

@jim_thompson5910 I really need this done like ASAP please like before 11:30 or midnight please and thank you sorry for rush

Answer 64

I got x = 30.48, but why do I need to simplify x/12 / 2.54 though

Answer 65

so it's f(x) = x/30.48

Answer 66

that's the answer for c

Answer 67

plug in a number of cm for x

out comes the measurement in feet

Answer 68

for part e, you will essentially think backwards

Answer 69

4C. should be (f o g)(x) = 30.48x right

Answer 70

sorry x/30.48

Answer 71

yeah

Answer 72

4d

Answer 73

looks good

Answer 74

I need help with 4E.

Answer 75

does my explanation work?

Answer 76

you use f(x) to go from cm to ft

you can also use it to go from ft to cm

Answer 77

is it yes or no

Answer 78

if you had x = 2.54, then you can figure out f(x) to get the number of ft

Answer 79

if you had some measurement of ft, you can replace f(x) with that number and solve for x to get the equivalent number of cm

Answer 80

is it a yes or a no for 4E.

Answer 81

yes I've been saying yes the whole time

Answer 82

@jim_thompson5910 do you mean f(x) or did you mean to say (f o g)(x)

Answer 83

oh right

I meant f(g(x))

Answer 84

or (f o g)(x)

Answer 85

How would you revise this: if you had some measurement of ft, you can replace f(x) with that number and solve for x to get the equivalent number of cm

Answer 86

well it's f(g(x)) and not f(x) like you said

Answer 87

it's like this

if T(x) helps you go from inches to ft, then

T(x) = x/12

plug in x inches to get T(x) ft

or

plug in T(x) ft and solve for x to get the inches

Answer 88

@jim_thompson5910 what's 3b's answer

Answer 89

did you use that link I sent you?

Answer 90

not really, don't know how to use it

Answer 91

I don't know what to plug in

Answer 92

the balance is 2000
the interest rate is 21.6% (since 1.8 times 12 = 21.6)
the monthly payment is 50

Answer 93

6 years it says

Answer 94

yeah 72 months