Question

fred begins walking toward johns house at 3mi/h. john leaves his house at the same time and walks towards fred house on the same path at a rate of 2mi/h. How long will it be before they meet if the distance between their houses is 4mi?

Answer 1

ok got it

Answer 2

so this is what it looks like right

Answer 3

k

Answer 4

wait like thats how u set it up or like how u write it

Answer 5

ok lets start over
fred=a
john=b

Answer 6

and forget about the drawing

Answer 7

alright

Answer 8

if fred walks 3mi/hr and john walks 2mi/hr then they walk a total of 5mi/hr correct

Answer 9

yes

Answer 10

so we can use the variable t for time so 3t+2t=4 correct

Answer 11

4t

Answer 12

wait no it equals 5t

Answer 13

yes so solve for t and what do you get?

Answer 14

solve 3t+2t=5t

Answer 15

so 5t=4 solve

Answer 16

t=1.25

Answer 17

if you divide both sides by 5 you get t=4/5

Answer 18

dont u divide 4 by 5. like 5 divided by 4

Answer 19

nope 4/5

Answer 20

how

Answer 21

lol idk how its just the way math works

Answer 22

its wierd though cause 5 has the variable. wouldnt u divide both sides by 5

Answer 23

yes you do divide both sides by 5 so you get t=4/5

Answer 24

oh i get it

Answer 25

lol

Answer 26

ya so now that you have 4/5hr. you need to convert that into min. do you know how to do that?

Answer 27

omg this is so much work. umm..sec into min, min into hours

Answer 28

really easy actually just multiple 60*(4/5)

Answer 29

i put 60 over 1?

Answer 30

yes and multiply across

Answer 31

k. so it will be 1200

Answer 32

no try this multiply 60 by 4
60*4

Answer 33

240. god im really kinda confused right now

Answer 34

ok now divide 240 by 5
240/5

Answer 35

u dont cross multiply because like the one ontop are the same thing so u have to multiply those together?? if it makes sense

Answer 36

48

Answer 37

yes thats your answer

Answer 38

dont u multiply240 by 5

Answer 39

oh i get it

Answer 40

no think of 4/5 as .8

Answer 41

uuhh now im really confused. i think imma ask my teacher tomorrow. I think dis is a problem that i need to see to understand. Thank u soo much though :D

Answer 42

im sorry dont know how to explain it any differently

Answer 43

this is what we did though
Let t=time spent walking until they meet
distance(d)=rate(r) times time(t) or d=rt;r=d/t and t=d/r
distance John walked=rt=3*t
distance Fred walked =rt=2*t
Now we know that when they meet, the distance John had walked plus the distance Fred had walked must equal 4 mi. So our equation to solve is:
3t+2t=4
5t=4 divide both sides by 5
t=4/5 hr or 48 min-------------time elapsed until they meet


CK
3*(4/5)+2*(4/5)=4 mi
12/5+8/5=4
20/5=4
4=4