Add up all of the side lengths and you get 148.4 as the perimeter.
subtract that from 150 and you're left with 1.6 m left of tape
Here I solved it for you on paper
Letter A? I think its letter A cause of the way its written above, I might be wrong but if i'm not let me know, have a great day :)
Answer:
r = 
Step-by-step explanation:
Express the equation with the term in r on the left side
P + Prt = A ( subtract P from both sides )
Prt = A - P ( isolate r by dividing both sides by Pt )
r = 