12. Let D D be a UFD. An element d ∈ D d∈D is a greatest common divisor of a a and b b in D D if d ∣ a d∣a and d ∣ b d∣b and d d is divisible by any other element dividing both a a and b . b. If D D is a PID and a a and b b are both nonzero elements of D , D, prove there exists a unique greatest common divisor of a a and b b up to associates. That is, if d d and d ′ d′ are both greatest common divisors of a a and b , b, then d d and d ′ d′ are associates. We write gcd ( a , b ) gcd(a, b) for the greatest common divisor of a a and b .

its 8

step-by-step explanation:

step-by-step explanation:

options

answer: 7 x 2/5 = 2.8 hours, is your answer. your welcome! : 3

step-by-step explanation: first work out how long it took to hose 1/7 of the lawn which is 2/5 hours. times that by 7 to get the whole lawn.

sorry i don't know the other answer. i didn't learn what a proportional relationship is.

she will sew have sewn five dresses   and be 1/3 done with the sixth one in an hour.

step-by-step explanation:

3/4 of an hour=45 mins

lucy makes 1 dress per 11.25 minutes

45 mins+11.25 mins=56.25 mins

60 mins- 56.25 mins=3.75 mins

3.75 mins is 1/3 of of 11.25 mins

therefore she the other 1/3 would be part of the hour and she will have sewn 5 dresses and begun the sixth.

contact me if you have any questions you are welcome.