Sunshine Primary School donated a batch of books to the mountainous area. If each primary school accepts a donation of 30 or 45 or 60 books, all of them will be donated. How many books are there in this batch at least?

30, 45 and 60 years old

The least common multiple is 180.

A: There are at least 180 books in this batch.

2.

Young Pioneers line up to do exercises, no matter how many 5 or 6 people in each row, they can form a rectangular team, and there is nothing extra. How many young pioneers are there at least? If the number is between 150 and 200, how many young pioneers are there?

The least common multiple of (1)5 and 6 is 30.

(2)30*5= 150 (person)

There are at least 30 young pioneers. If the number is between 150 and 200, there are 150 young pioneers.

3.

Three students are not in the same class. A is on duty every four days, B is on duty every five days and C is on duty every six days. Last time they were on duty on the same day on Wednesday. How many days do they need to be on duty that day? What day is today?

The least common multiple of 4, 5 and 6 is 60.

60/7=8+4

3+4=7

answer

Wait for another 60 days to be on duty that day, which is Sunday.

4.

When two numbers are multiples (such as 9 and 18), how to find the least common multiple of these two numbers.

When two are multiples, a large number is their least common multiple.

Such as 9 and 18.

18 is their least common multiple.

5.

Find the least common multiple of the following groups.

12 and 8

Articles 5 and 7

Articles 6 and 48

10 and 15

The least common multiple of 12 and 8 is 24.

Articles 5 and 7

The least common multiple of is 35.

Articles 6 and 48

The least common multiple of is 24.

10 and 15

The least common multiple of is 30.

6.

What are the common multiples of 2 and 5? What are the characteristics of common multiples of 2 and 3? What are the characteristics of common multiples of 2, 5 and 3?

( 1)

The unit is 0 (2)

Is a multiple of 6 (3)

Is a multiple of 30.

7.

What is the greatest common factor of 75 and 30?

The greatest common factor of 75 and 30 is 15.

8. Two sticks, the first one 1 length16m, and the second one is 24m long. Cut them into small pieces of the same length, and there should be no excess. What is the longest length of each stick? How many segments can a * * * be cut into?

The greatest common factor of 16 and 24 is 8.

(

16+24)/8=5 (paragraph)

A: Each small stick is 8 meters long, and one * * * can cut 5 sticks.

9. The rectangle is 20m long,12m wide and 8m high. Cut it into cubes of the same size, as big as possible. How long are the sides of this cube?

?

The greatest common factor of 20,12,8 is 4.

The side length of this cube is 4 meters.