Answer:
7/15
Step-by-step explanation:
7 boxes out of 10 contain $20. Therefore 3 boxes do not have $20 bills.
The probability of picking a bag with a $20 bill
= 7/10
The probability of picking another bag with $20 bill
= (7-1)/(10-1)
= 6/9
The probability of getting two $20 bills.
= 7/10 × 6/9
= 42/90
= 7/15
