Mother's age is four times that of Xiaoli now, and ten times that of Xiaoli six years ago. Please figure out the age difference between mother and Xiaoli?

Let Xiao Li be x years old
(4x-6)/10=x-6
2/5x-0.6=x-6
2/5x=x-5.4
3/5x=5.4
x=9
9 * 4 = 36 years old
A: Xiaoli is 9 years old and her mother is 36 years old. Six years ago, Xiaoli was 3 years old and her mother was 30 years old

Mother takes a day off after three days' work, and father takes a day off after four days' work
How many days at least can they have a rest at the same time? Can they have a rest at the same time on June 1?

This study is about the common multiple. The real time for parents to rest at the same time must be the common multiple of their work and rest time, that is to say
The next time they have a rest together is May 20. They can't have a rest at the same time on June 1

Xiaoming's father takes one day off every six days, and his mother takes one day off every four days. On May 2, they take a day off together and ask when they can take another day off together

The least common multiple of 7 and 5 is 35. That is to say, we have a rest every 35 days. There are 29 days left in May, and another 6 days, that is, we have a rest again on June 6

Dad takes a day off every 5 days. My mother takes a day off every 2 days. On the children's day, father and mother rest at the same time.

If it's dad's day 5 break: June 11
If it's dad's Day 6 break: June 7

Mother's age is four times that of Xiaoli now, and ten times that of Xiaoli six years ago. Please figure out the age difference between mother and Xiaoli?