Question

a beg contain 6 white, 5 red, and 4 black balls. in how many ways 4 balls can be selected that at least 2 black balls​

Answer 1

a bag have total balls....6+5+4 =15

u select 4 balls so..

total possiblity = ¹⁵c4 = 1365

know ...

at least two balls means .. two or three or four...

1) if 2 is black.. ⁴c2× ¹¹c2 = 330

2) if 3 is black.. ⁴c3×¹¹c1 = 44

3) if all 4 black... ⁴c4 = 1

so .. 330+44+1 = 375

your final ans.. 375/1365

plese like ans..