An unknown substance weighs 26.28kg when it is first brought to the lab. after a week in the lab, a technician weighs it again and finds it weighs 9.47kg. assuming the substance is decaying exponentially, calculate the decay factor from week to week.

Decaying rate is 6.3965% per week.

Step-by-step explanation:

Given that an unknown substance weighs 26.28kg when it is first brought to the lab. After a week in the lab, a technician weighs it again and finds it weighs 9.47kg.

Since we assume the substance is decalying exponentially let us assume decay rate is r%

, where t represents the number of weeks form the beginning.

When t=1, P = 9.47

Substitute to get

Decaying rate is 6.3965% per week.

he spend 5.1 minutes chatting with his friends

step-by-step explanation:

2/5+1/2=9/10

6/1-9/10=5 1/10