Will mark brainliest and give 20 points!

Im not sure if you need the work, but the answer is 3.8 hours. you make them into fractions, like in one hour ann could build 1/5 of the model car and sam 1/15 of the car. you use that to then find 1/x (how much they could build together) and multiply by the lcd. Its complicated sorry i cant explain well lol

Well kind of you would have to split the remainder
3/5 = 1 with a remainder of 2