5. 36kg of rice was reduced, resulting in a 3/5 reduction of rice, but the number of non-rice grains remained unchanged, so the ratio of rice to non-rice was (3/4)/( 1-3/4)=3 at first, and it was (3/5)/(1-3 after eating 36kg of rice.

36/ 1.5=24kg, and raw grain 24/( 1-3/4)=96kg.

(All comrades who answered 240kg! ! ! The total amount is also changing! ! ! You can't do this! ! ! )

6. According to the topic, dad started late 10 minutes, so it is equivalent to a catching-up problem, that is, dad started early 10 minutes, and dad 2 caught up with dad 1 3 times (that is, running speed). So 10/(3- 1)=5 minutes later, Dad 2 catches up with Dad 1, that is, half of the total distance is completed, so it takes Dad 10+5 = 15 minutes to complete the whole journey, so the time should be 60 minutes.