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.
Answer:
A = 58.7 degrees
B = 66.9 degrees
C = 34.1 degrees
Step-by-step explanation:
<u><em>For <A:</em></u>
Tan A = 
Tan A = 
Tan A = 1.6
A = 
A = 58.7 degrees
<u>For <B:</u>
Sin B = 
Sin B = 
Sin B = 0.92
B = 
B = 66.9 degrees
<em><u>For <C:</u></em>
Sin C = 
Sin C = 
Sin C = 0.56
C = 
C = 34.1 degrees