I'm not sure what exactly you mean by from but maybe addition or division
Probability that first student prefers mechanical pen = 0.30
P(first student does not and second student does) = 0.70 * 0.3 = 0.21)
P( selecting 2 or fweer) = 0.30+ 0.21) = 0.51 or 51%
Answer:the answer is C
Step-by-step explanation:
Okay add 78 and 66. Then add 96 and 108. It should be 144 by 204. I know math is hard, but when you work at it you can do amazing things! I hope that helps you.
You wanna find a common denominator so put the problem like this
3 1/3.< You wanna take 3 (denominator)
And times it
By 5 then you wanna take the 5. - 2 2/5.< (deniminator) and times it by 3.
____ Your common denominator is 15
now it will look like this
3 1/15
-2 2/15
———-
Now subtract. You will need to borrow 1 from 3 since you cant subtract 2 by 1 so the 3 will become a 2 and the 1 will be come 11 and here you can subtract so this will be your answer.
2 11/15
-2 2/15
-———-
0 9/15
Thats your official answer 9/15 hope I helped :)