For what fraction of a day will a 12-hour digital clock that shows only the hours and minutes display at least one 5 or 6

4/9

Step-by-step explanation:

Find out combinations without 5 or 6.

Minutes with 5 or 6: 05,06,15,16,25,26,35,36,45,46,50–59. It 10+10=20 minutes per hour. And 40 minutes without 5 or 6.

Hours with 5 or 6: 5 and 6. Without 5 and 6 is 0,1,2,3,4,7,8,9,10,11 (10 hours).

Total time without 5 and 6 is 10*40minutes=400 minutes.

Time with 5 or 6 is 12*60–400=320 minutes.

Fraction of a day: 320/(12*60)=4/9=0.44444

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

answer: i think you should do the math and pay attention in class : )

step-by-step explanation:

that is truly what   think but if i get the answer i will