The answer is <span>She went over by one over six of a cup
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<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.
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Answer: 0.4 which is choice C
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Work Shown
Focus on the "riverside high school" row only
A = number of twelfth graders = 200
B = number of students = 500
P = probability of picking a twelfth grader
P = A/B
P = 200/500
P = 2/5
P = 0.4
Just substitute in the number 3 for x then subtract 3 at both sides and youll have y=7
WXY = XYW ( = 41 ) ⇒ XYW is a isosceles triangle
⇒ XW = YW
⇒ 54 = 6x + 6
⇒ 6( x + 1 ) = 54
⇒ x + 1 = 9
⇒ x = 8
ok done. Thank to me :>
