Direct variation is is when the x and y a direct relation
without constants added or subtracted
With being times by each other
so the only one that meets the definite is the first one
y = 0.5x means y is equal to half of x. So you know that every y is directly related to half of x
So, to set up this equation, lets just say that Lucas did 5 hours of homework also. The ratio of Lucas's homework to video games is 60 minutes of homework/30 minutes of video games. If we converted the 5 hours into 300 minutes then you would multiply the 60 minutes by 5 and the 30 minutes by 5 also. You would get 300 minutes/150 minutes. Jonathan's ratio is every 5 hours of homework/3 hours of video games. We would convert this to minutes by taking both numbers and multiplying them by 60. We would get 300 minutes/180 minutes. Using this we know that Jonathan gets more time to play video games because every 5 hours of homework he gets 180 minutes of gaming and for Lucas, every 5 hours of homework he only gets 150 minutes of gaming. I hope that this helped you!
Answer:
Let AB be the flagstaff and CD be the vertical tower.
AB=10m=EC
BC=20m=AE
In triangle ABC we have,
tanx=AB/BC
tanx=10/20
1/tanx=20/10
10/tanx=20...........1
In triangle ADE we have
tan(90-x)=DE/AE
cotx=DE/20
1/cotx=20/DE
DE/cotx=20..............2
by eq1 and. eq 2 we get
10/tanx=DE/cotx
10/(AB/BC)=DE/(BC/AB)
10/(10/20)=DE/(20/10)
10×20/10=DE×10/20
DE=40m
Therefore height of vertical tower = DE+EC=40+10=50m
The answer is the last option
Ratio tables are like proportional relationships (if you know what that is), and you have to do this:
6:9 is related to a:45 we don't know a, but since the prior ratio is related to this one, you simply take 9 times what is 45. The answer is 5, so then you multiply 6 times 5 to get 30. Then keep building off of that. The next problem will be 48, then 72.
The bottom ratios start with 10:15. 15 times 3 is 45 so 10 times 3 is 30. The next one is 100, then 70. Hope this helps, sorry that it's confusing!