The probability that a student passes an examination is 2/5. if two students are picked at random from the class, what is the probability that one of them will pass and the other one will fail?

12/25

Step-by-step explanation:

There are four possibilities, P=Pass, F=Fail:

The chance of failing is 1-2/5 = 3/5.

PP = 2/5 * 2/5  = 4/25

PF = 2/5 * 3/5 = 6/25

FP = 3/5 * 2/5 = 6/25

FF = 3/5 * 3/5 = 9/25

(note that these chances add up to 1, as they should!)

We are interested in PF or FP, the sum of those is 6/25 + 6/25 = 12/25

So generally, when you say "AND" you multiply chances, and when you say "OR" you add them.

So (student 1 Passes AND student 2 Fails) OR (Student 1 Fails AND student 2 Passes)

hello :

70y^8 + 30y^6 = 2 ( 35 y^8 + 15y^6)

the lenght is : 35 y^8

the width is : 15y^6

30 miles

step-by-step explanation:

we know that 60 seconds equals 1 minute and 60 minutes 1 hour

44 ft       60 sec     60 min     158400   ft

  *   *   =

1 sec       1 min       1 hour         hour

we know that there are 5280 ft per mile

158400   ft       1 mile         30 miles

  *   =

1   hour               5280 ft     1 hour

so in 1 hour   it can travel 30 miles