How to find the greatest common factor and the least common multiple, we need to formulate

Bracket that is the way of expression, the greatest common cause use bracket (18 27) = 9
The least common multiple is in bracket [18 27] = 54

Greatest common factor, least common multiple
1. The number of students in Grade 5 participating in tree planting activities is less than 100. Divide all students into groups. If every two students form a group, there will be two students left; if each group has four students, there will be three students left; if each group has five students, there will be four students left. How many students in Grade 5 participate in tree planting activities?
2. Class 5 (1) has 3 students in each line, 2 students in the last line are less, 4 students in each line, 3 students in the last line are less, 5 students in each line. As a result, there is only 1 student in the last line. How many students are there at least in class 5 (1)?
3. There are more than 50 students in class 5 (1) going to clean up. They are divided into 4 groups with more than 2 students on average and 5 groups with more than 3 students on average?
4. There are a number of saplings, 9 in a bundle, 7 in a bundle, 10 in a bundle, 8 in a bundle, 12 in a bundle, 10 in a bundle. These saplings range from 150 to 200. How many saplings are there in total?
5. There are three wires, which are 12 meters, 44 meters and 56 meters long respectively. They should be cut into small sections of the same length, and no surplus is allowed. How long is the maximum length of each small section of wire?
6. People's Square is the starting point of No.1, No.5 and No.7 bus. No.1 bus leaves every 5 minutes, No.5 bus leaves every 8 minutes, No.7 bus leaves every 10 minutes. After these three buses leave at 7 am at the same time, how many minutes will they leave at the same time? What time is it?
7. A piece of rectangular paper, 90cm in length and 60cm in width, can be cut into a square of the same size with the side length of the whole centimeter without surplus. At least how many pieces can be cut?
9. There is a kind of rectangular glass 12 cm in length and 8 cm in width. If you use this kind of glass to make a square, how many pieces do you need at least?

It is impossible that there is a conflict between two people in a group of 1,2 and three people in a group of 4. The result of adding 1 to the least common multiple of 2,3,4,5 should be 61 people. The result of subtracting 2 from the least common multiple of 3,4,5 is 18 people. The result of subtracting 2 from the common multiple of 4,9,10,12 is 178 trees. 5

A. The greatest common factor of B is 12 and the least common multiple is 144. What are the two numbers?
What's the formula

144/12=12=1*12=3*4
These two numbers are
1*12=12
12*12=144
perhaps
3*12=36
4*12=48

The greatest common factor of two numbers is 12 and the least common multiple is 144. One of them is 36 and the other is ()
A. 156B. 12C. 48D. 132

Because 144 △ 12 = 12, 12 = 1 × 12 = 2 × 6 = 3 × 4, there are three cases of these two numbers: 12 × 1 = 12, 12 × 12 = 144 or 12 × 2 = 24, 12 × 6 = 72 or 12 × 3 = 36, 12 × 4 = 48, so one of them is 36, and the other is 48; therefore, C

How to find the greatest common factor and the least common multiple, we need to formulate