N₁*$0.10 + n₂*$0.25 = $2.25
n₁ + n₂ = 12
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This means that:
n₁ = 12 - n₂
And:
(12 - n₂)*$0.10 + n₂*$0.25 = $2.25
12*$0.10 - n₂*$0.10 + n₂*$0.25 = $2.25
$1.20 + n₂*$0.05*(5-2) = $2.25
$1.20 + n₂*$0.05*3 = $2.25
$1.20 + n₂*$0.15 = $2.25
n₂*$0.15 = $2.25 - $1.20
n₂*$0.15 = $1.05
n₂ = ($1.05)/($0.15)
n₂ = 7
If n₂ = 7:
n₁ + 7 = 12
Therefore, n₁ = 5.
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Answer:
5 dimes and 7 quarters.
Answer:
SteThe redwood is 3.75 times thicker
p-by-step explanation:
Answer:
19/42
Step-by-step explanation:
multiply each fraction by the opposite denominator to get the same denominator for both 12+7=19 &6×7=42
Answer:
x = 13
y = 15
Step-by-step explanation:
ST = DT ( Reason : from given )
5x = 65
x = 65 / 5
x = 13
TY = TU ( Reason : from given )
3y + 5 = 50
3y = 50 - 5
3y = 45
y = 45 / 3
y = 15
Comment
This is an area problem. The key words are 120 square feet and 12 feet longer.
And of course width is a key word when you are reading this.
Formula
Area = L * W
Givens
W = W
L = W + 12
Substitute and Solve
Area = L* W
120 = W*(W + 12)
W^2 + 12W = 120 square feet
w^2 + 12w - 120 = 0
This does not factor easily. I would have thought that a graph might help but not if the dimension has to be to the nearest 1/100 of a foot. The only thing we can do is use the quadratic formula.
a = 1
b = 12
c = - 120
w = [ -b +/- sqrt(b^2 - 4ac) ]/(2a)
w = [-12 +/- sqrt(12^2 - 4*(1)(-120)] / 2*1
w = [-12 +/- sqrt(144 - (-480)]/2
w = [-12 +/- sqrt(624)] / 2
w = [- 12 +/- 24.979992] / 2 The minus root has no meaning whatever.
w = (12.979992) / 2
w = 6.489995 I'll round all this when I get done
L = w + 12
L = 6.489995 + 12
L = 18.489995
check
Area = L * W
Area = 6.489995*18.489995
Area = 119.999935 The difference is a rounding error
Answer
L = 18.489995 = 18.49 feet
W = 6.489995 = 6.49 feet
Note: in the check if you round first to the answer, LW = 120.0001 when you find the area for the check. Kind of strange how that nearest 1/100th makes a difference.
