If x represents the width of the poster (including borders), the area of the finished poster can be written as
.. a = x*(390/(x -10) +8)
.. = 8x +390 +3900/(x -10)
Then the derivative with respect to x is
.. da/dx = 8 -3900/(x -10)^2
This is zero at the minimum area, where
.. x = √(3900/8) +10 ≈ 32.08 . . . . cm
The height is then
.. 390/(x -10) +8 = 8 +2√78 ≈ 25.66 . . . . cm
The poster with the smallest area is 32.08 cm wide by 25.66 cm tall.
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In these "border" problems, the smallest area will have the same overall dimension ratio that the borders have. Here, the poster is 10/8 = 1.25 times as wide as it is high.
Answer:
16 quarters
30 pennies
Step-by-step explanation:
q= quarters
p=pennies
set up a system of equations. One equation is for total value, the other is total # of coins.
q + p = 46
0.25q + 0.01p = 4.30 -> multiply this equation by 4 so you can subtract from the top equation
q + P =46
1q + 0.04p = 17.20
subtract the bottom equation from the top
0.96p = 28.8
divide by 0.96
p=30
substitute p in the top equation
q + 30 = 46
subtract 30 from both sides
q = 16
When it says 7/10, it actually means 70%, so you have to find 70% of 120.
<span>
70 % of 120
= 70% x 120
= (70/100) x 120
= (8400/100)
= 84
Answer: 84</span>
I think b not sure it’s the only one that makes sense
Answer:
172
Step-by-step explanation:
The formula for the missing term of a geometric sequence is the square root of x times y.