The greatest common divisor of a and B is 8, and the least common multiple is 560. One of them is 80, and what is the other? (to calculate the formula)

The greatest common divisor of a and B is 8, and the least common multiple is 560. One of them is 80, and what is the other? (to calculate the formula)

The least common multiple is 560, one is 80, and the other must be 560 / 80 = 7
The greatest common divisor is 8, so this number is also a multiple of 8
So this number is a common multiple of 7 and 8, so it's a multiple of 56
We can know that 56 meets the requirements

Thank you. If a = 3 × 3 × 5, B = 2 × 3 × 5, then the greatest common divisor of a and B is the least common multiple

The greatest common divisor of a and B is 3 * 5 = 15, and the least common multiple is 2 * 3 * 3 * 5 = 90
(1) How to find the greatest common divisor
In the method of decomposing prime factors, the prime factors of two numbers are written and all the common prime factors of several numbers are multiplied;
For example, find the least common multiple of 45 and 30
45=3*3*5
30=2*3*5
Multiply the common prime factor, then the greatest common divisor = 3 * 5 = 15
(2) The method of finding the least common multiple
First of all, write out the prime factors of two numbers, and the least common multiple is equal to the product of all their prime factors (if several prime factors are the same, compare which of the two numbers has more prime factors and multiply more times)
For example, find the least common multiple of 45 and 30
45=3*3*5
30=2*3*5
The different prime factors are 2, 3 and 5.3, which are both of them. Because 45 has two 3's and 30 has only one 3's, the least common multiple is multiplied by two 3's
The least common multiple is equal to 2 * 3 * 3 * 5 = 90

Several mathematical problems of greatest common divisor and least common multiple
1. A = 2 × 3 × 7, B = 2 × 5 × 7, the greatest common divisor of a and B is () and the least common multiple is ()
2. If a number is divided by 4, 5 and 6, the minimum number is ()
3. The greatest common divisor of 12, 18 and 20 is ()
①2 ②4 ③12 ④180

1.14 2102.613. ① the greatest common divisor of 2 is the largest number that can be divided by a pile of numbers. Just find the same factor and multiply it. For example, in question 1, both a and B have 2 and 7, so the greatest common divisor is 14

1 and 8 greatest common factor () least common multiple () 10 and 2 least common multiple () 18 and 13 greatest common factor () 31 and 62 greatest common factor ()
1 and 8 greatest common factor () least common multiple ()
Least common multiple of 10 and 2 ()
18 and 13 greatest common factor ()
31 and 62 greatest common factor ()

1 8
ten
one
thirty-one

The greatest common factor and the least common multiple of 10,12,18,

∵10=2*5
12=2*2*3
18=2*3*3
The greatest common factor is 2
Least common multiple 2 * 5 * 2 * 3 * 3 = 180

4. The greatest common divisor of 8, 12, 16 and 20 is () and the least common multiple is ()
It's better to use prime number decomposition

4. The greatest common divisor of 8,12,16,20 is (4), and the least common multiple is (240)
16 is a multiple of 4 and a multiple of 8
12=2×2×3
16=2×2×2×2
20=2×2×5
The least common multiple is 2 × 2 × 3 × 2 × 2 × 5 = 240

The least common multiple of 16.96.20

The least common multiple is 480

16 and 20 calculate the least common multiple by decomposing prime factor

16=2x2x2x2
20=2x2x5
The qualitative factors of 16 and 20 are 2 and 2
16 unique quality factor: 2, 2
20 unique quality factor: 5
The least common multiple of 16 and 20: 2x5 = 80

The greatest common divisor of 6 and 15 is______ The least common multiple is______ ．

4 = 2 × 2, 6 = 2 × 3, 15 = 3 × 5, so the greatest common divisor of 4, 6 and 15 is 1, and the least common multiple is 2 × 2 × 3 × 5 = 60

The greatest common divisor of two numbers is 6 and the least common multiple is 504. If one of the numbers is 42, what is the other number?

504 △ 42 = 12, 12 × 6 = 72, a: the other number is 72