Ok! At first Laurie has 40 candies since 4 times 10 is 40. then after her dad gives here more, she has 45.
45 is not divisible by six, so we will get a remainder. the closest number to 45 when multiplied by six is 42, and 42/6=7.
Each friends will get 7 pieces, and there will be a remaining of 3 pieces since 45-42=3.
Hope it helped!