hectictar

volume of cylinder = pi * (diameter/2)² * height

BTUs per cubic foot = total number of BTUs / total number of cubic feet

750 BTUs/person  *  15 people   =   11,250  BTUs   total

38 ft * 8.5 ft * 6.25 ft   =   2018.75   cubic feet   total

11,250 BTUs / 2018.75 cubic feet  ≈    5.573    BTUs per cubic foot

Wow really! Hey it's a good thing to know how to do! 

Hmmm...how about...

Solve for x.

ax² + bx + c = 0

You will need to "complete the square" to get the answer.

I think this is probably algebra II level, but I'm not sure.

Or maybe you've done this already...

I think you want the measure of the arc DF 

\(\angle{DEF}=\frac12\,\cdot\,\overset{ \frown}{DF} \\~\\ 72^{\circ}=\frac12\,\cdot\,\overset{\frown}{DF} \qquad \text{ Multiply both sides of the equation by 2.} \\~\\ 144^{\circ}=\overset{\frown}{DF}\)

That is pretty cool Z !!!!  👍

Also, you might have seen that trick about how to remember the multiples of 9 before....

One time I wondered what would it do if I just continued the list past 90.

The first column counts up, the second column counts down. Whenever you reach zero in the second column, repeat the number in the first column.

0    9

1    8

2    7

3    6

4    5

5    4

6    3

7    2

8    1

9    0

9    9

10  8

11  7

12  6

13  5

14  4

15  3

16  2

17  1

18  0

18  9

19  8

20  7

21  6

22  5

23  4

...

Let's fast forward to " 909 "

...

90  9

91  8

92  7

93  6

94  5

95  4

96  3

97  2

98  1

99  0

99   9

100 8

101 7

102 6

103 5

...It still works !!  I don't know why, but for some reason I find this neat LOL 

surface area = [ (circumference of base) * (height) ]   +   [ 2 * (area of base) ]

So...

surface area = [ 2 π r h ] + [ 2 π r² ]       , where  r  is the radius and  h  is the height of the cylinder.

Which part of the pyramid is 5.7 yards ?

Is it the length of one side of the base, is it the height of the pyramid, or is it the slant height ?

Which parts of the pyramid is 5.1 yards, 3 yards, and 6 yards  ?

12 * 1 = 12    \(\leftarrow\)     not a multiple of 5

12 * 2 = 24    \(\leftarrow\)     not a multiple of 5

12 * 3 = 36    \(\leftarrow\)     not a multiple of 5

12 * 4 = 48    \(\leftarrow\)     not a multiple of 5

12 * 5 = 60    \(\leftarrow\)     this is a multiple of 5

So...the least common multiple of 5 and 12 is 60

Tom used 13% of the can

Lisa used  0.6  of a pound

Jane used 0.12 of the can

Let's convert Tom and Janes values into pounds so we can compare them.

How many pounds is 13% of the can?

How many pounds is 13% of 4 pounds?

13% of 4 pounds   =   0.13 * 4  pounds   =   0.52  pounds

How many pounds is 0.12 of the can?

How many pounds is 0.12 of 4 pounds?

0.12 of 4 pounds   =   0.12 * 4  pounds   =   0.48  pounds

So...

Tom used  0.52  pounds

Lisa used  0.6    pounds

Jane used 0.48  pounds

0.6  is bigger than  0.52  and  0.48 . Lisa used the most sugar.