A=pR^2-2pr^2, since R=15 and r=7.5
A=225p-112.5p
A=112.5p
A≈353.25 ft^2
X = 1 hr lessons and y = 1/2 hr lessons
x + y = 35......y = 35 - x
40x + 25y = 1115
40x + 25(35 - x) = 1115
40x + 875 - 25x = 1115
40x - 25x = 1115 - 875
15x = 240
x = 240/15
x = 16 <=== there are 16 one-hr lessons
and 19 half-hr lessons
The model for representing the ratio of the number of orange and green rolls are
.
A model that shows the number of orange and green streamers needed to decorate 3 dorm rooms will be 3O=2G
<h3>What is ratio?</h3>
The ratio is defined as the representation of the one number with respect to the other number. or one number is how many times to the other number.
A model that represents the ratio of different colored streamers.

A model that shows the number of orange and green streamers needed to decorate 3 dorm rooms.
D=3O and D=2G
3O=2G
Hence the models are
and 3O=2G.
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