Card in a pack are black and red in a ratio black: red=2: 5 what fraction of the cards are red a)7/10 b)2/5 c)5/7 d)2/7

me to why is 5/7?

c. 5 / 7

Step-by-step explanation:

Ratio of Black to Red of 2 : 5 means in a total of 7 cards, you will get 2 Black and 5 Red cards.

So, fraction of Red cards will be total number of possible Red cards divided by total number of all cards

1.e 5 / 7

15%

step-by-step explanation:

use the table and count the number of guesses that has two correct answers.

the following are two correct answers

10010, 01100, 11000

a total of 3 numbers having 2 correct guesses out of 20 questions.

probability of getting 2 correct guesses = the number of questions getting 2 correct answers / total number of questions.

= 3/20

to convert it into percent multiply by 100, we get

= 3/20 * 100

= 15%

the answer is 15%

you.