In this question, you are given the volume of cylinder (24

cubic unit) and the ratio of the height:radius (3:1). Putting it into equation, it will look like this:
volume= 24

cubic unit
height = 3 radius
radius = 1/3 height
Using the volume formula of cylinder you will got the height
Volume=

* radius * radius * height
24

cubic unit =

*(1/3 height) * (1/3 height) * height
24

cubic unit /

= 1/9 height cubic
1/9 height cubic = 24 cubic unit
height cubic = 24*9= 216 cubic unit
height=∛216 cubic unit= 6 unit
You start with 75 houses
2/5 were sold, which mean 3/5 remain
3/5 of 75 is 45
Then, 1/3 of the REMAINING (45) houses were sold. Since 1/3 were sold, 2/3 remain of 45.
2/3 of 45 is 30
30 houses are left to be sold
A) okay so let x represent how old the friend is now. And 4 represent the years added on. If you have to be LESS then 18 years old to be in boy scouts, and the friend is still able to be in boy scouts after four years, then It can be modeled by x + 4 < 18
B) wrote down number values with 18 being in the middle. Plot a dot on the number 18 (with an open circle. Not filled in circle. A filled in circle means equal to and it is not equal to.) and since you have to be LESS then 18, you should draw a line going left to the smaller numbers of 18.
I hope this helps??
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