Question

A box contain 8 black balls 12 white balls. Another box contain 9 black and 6 white balls .one ball from each box is taken .
a)what is the probability that both being black balls ?
b)what is the probability of getting one black and one white ball?​

Answer 1

Answer:

13/25

Step-by-step explanation:

First box contains 8 black and 12 white beads Second box contains 9 black and 6 white beads.

(a) One black bead from each box is taken.

Number of such cases = 8×9=72

Total number of possibilities = 20×15=300

Probablity of getting both black beads =

300

First box contains 8 black and 12 white beads Second box contains 9 black and 6 white beads.

(a) One black bead from each box is taken.

Number of such cases = 8×9=72

Total number of possibilities = 20×15=300

Probablity of getting both black beads =

72/300 =6/25

(b) One black and one white bead is taken.

So if one black bead is taken from first box then one white bead is taken from second box and if one white bead is taken from first box then one black bead is taken from second box.

Number of such cases = 8×6+12×9=48+108=156

Total number of possibilities = 20×15=300

Probablity of getting one black and one white bead=

156/300=13/25

Answer 2

Answer:

(a) 72/300 =>12/50

(b)((8*6)+(12*9)/300)=((48+108)/300)=156/300=>26/50

Step-by-step explanation:

(a) number of chances that both being black balls =8*9=72

total number of chances =20*15=300

there for probability of both being black ball =72/300

(b) there is two combination of chances

first ball white and second ball black

first ball black and second ball white

there for total combination of chances is equal to 8*6+12*9=156

total number of chances =20*15=300

there for probability of both being=156/300=>26/50