Answer:
C. 666
Step-by-step explanation:
USING PEMDAS we can solve this problem.
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A. 12*x + 2*y = 90
6*x + 2*y = 60
To write system of equation you just need to sum all solo and ensemble acts and make it equal to how much they will last for.
B. Here we can multiply second equation with negative 1 and add it to first equation.
6x = 30
x = 5
now we replace x in any of 2 equations to get y.
30+2y = 60
2y = 30
y=15
Solo acts are 5 minutes long and ensemble acts are 15 minutes long
The answer is <span>She went over by one over six of a cup
</span>
<span>1 cup of that particular chocolate powder has a mass of 128 grams: 1c = 128g
</span><span>64 grams of chocolate powder is x cups.
1c = 128g
x = 64g
1c : 128 g = x : 64g
x = </span>1c : 128 g * 64 g
x = 0.5 c
64 grams of chocolate powder is 0.5 cups = 1/2 cups
<span>She added two over three of a cup of chocolate powder: 2/3 cups
She need to add 1/2 cups: 1/2 = 3/6 cups
She added 2/3 cups: 2/3 = 4/6 cups
So she added 4/6 - 3/6 = 1/6 cups more.
</span>
To write it in simplest form, you must find a common factor.
In
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, 3 is a factor of both 3 and 9
3÷3=1 and 9÷3=3
So
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is your answer in simplest form.
-10.6, and 9/10, are the constants