Traci is running a trail in hanna park. she can run one mile in ten minutes. yoni is running the same trail as traci. yoni can run a mile in five minutes but starts running 20 minutes after traci started on the trail. if they start the trail from the same point, how long will it take yoni to catch traci

Yoni will catch Traci after 20 minutes.

Step-by-step explanation:

Let Yoni will catch traci after t minutes.

The speed of Traci is miles per minute.

The speed of Yoni is miles per minute.

Yoni run for t minutes, so distance covered by Yoni in t minutes is

Traci run for (t+20) minutes, so distance covered by Traci in (t+20) minutes is

Yoni will catch traci, if

Multiply both sides by 10.

Therefore, Yoni will catch Traci after 20 minutes.

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