Answer: d
Step-by-step explanation:
The probability of not being purple is the probability of the three other colors. Suppose the number of purple marbles is x. Then we have 20+30+40+x = 90 + x marbles. Then the probability of not being purple is 90/(90+x). If this fraction can have a lowest term for some value of x, then the numerator of this lowest term must be a factor of 90.
Checking through the options, only option D has a non-factor of 90 as its numerator.
Its b= -0.2 or b= 1/-5 whichever one works best
Use this equation: A=3.14159r^2
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Answer:</u></h2><h2><u>
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Solution Steps:</u></h2>
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<h3>1.) Combine like terms:</h3>
<em> - We do this because we need 1 Number/Variable left over. </em>
<u>Equation at the end of Step 1:</u>
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<h3>2.) Add −17 and 31:</h3>
<em> - We do this because we can only have 1 number on each side of the equals. (This doesn't count towards the number connected to the variable.)</em>
<u>Equation at the end of Step 2:</u>
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<h3>3.) Subtract 14 from both sides:</h3>
Cancels Out
<em> - We do this because now we just need the 1 variable and the 1 number on opposite sides of the equal.</em>
<u>Equation at the end of Step 3:</u>
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<h3>4.) Multiply both sides by 2:</h3>
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<em> </em>×
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<em> </em>× 
<em> - We multiply by 2 since we have a fraction. In this case the reciprocal is 2 meaning we multiply by 2. </em>
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Your conclusion would equal
x = 5