To find all the divisors of the number 99,900:
- 1. Decompose the number into prime factors.
- See how you can find out how many factors (divisors) the number has, without actually calculating them.
- 2. Multiply the prime factors in all their unique combinations, that yield different results.
1. Carry out the prime factorization of the number 99,900:
The prime factorization of a number: finding the prime numbers that multiply together to make that number.
99,900 = 22 × 33 × 52 × 37
99,900 is not a prime number but a composite one.
- Prime number: a natural number that is divisible (divided evenly) only by 1 and itself. A prime number has exactly two factors: 1 and the number itself.
- Examples of prime numbers: 2 (factors 1, 2), 3 (factors 1, 3), 5 (factors 1, 5), 7 (factors 1, 7), 11 (factors 1, 11), 13 (factors 1, 13), ...
- Composite number: a natural number that has at least one factor other than 1 and itself. So it is neither a prime number nor 1.
- Examples of composite numbers: 4 (it has 3 factors: 1, 2, 4), 6 (it has 4 factors: 1, 2, 3, 6), 8 (it has 4 factors: 1, 2, 4, 8), 9 (it has 3 factors: 1, 3, 9), 10 (it has 4 factors: 1, 2, 5, 10), 12 (it has 6 factors: 1, 2, 3, 4, 6, 12), ...
How to count the number of factors of a number?
Without actually finding the factors
- If a number N is prime factorized as:
N = am × bk × cz
where a, b, c are the prime factors and m, k, z are their exponents, natural numbers, .... - ...
- Then the number of factors of the number N can be calculated as:
n = (m + 1) × (k + 1) × (z + 1) - ...
- In our case, the number of factors is calculated as:
- n = (2 + 1) × (3 + 1) × (2 + 1) × (1 + 1) = 3 × 4 × 3 × 2 = 72
But to actually calculate the factors, see below...
2. Multiply the prime factors of the number 99,900
- Multiply the prime factors involved in the prime factorization of the number in all their unique combinations, that give different results.
- Also consider the exponents of these prime factors.
- Also add 1 to the list of factors (divisors). All the numbers are divisible by 1.
All the factors (divisors) are listed below - in ascending order
The list of factors (divisors):
Numbers other than 1 that are not prime factors are composite factors (divisors).
neither prime nor composite =
1
prime factor =
2
prime factor =
3
composite factor = 2
2 =
4
prime factor =
5
composite factor = 2 × 3 =
6
composite factor = 3
2 =
9
composite factor = 2 × 5 =
10
composite factor = 2
2 × 3 =
12
composite factor = 3 × 5 =
15
composite factor = 2 × 3
2 =
18
composite factor = 2
2 × 5 =
20
composite factor = 5
2 =
25
composite factor = 3
3 =
27
composite factor = 2 × 3 × 5 =
30
composite factor = 2
2 × 3
2 =
36
prime factor =
37
composite factor = 3
2 × 5 =
45
composite factor = 2 × 5
2 =
50
composite factor = 2 × 3
3 =
54
composite factor = 2
2 × 3 × 5 =
60
composite factor = 2 × 37 =
74
composite factor = 3 × 5
2 =
75
composite factor = 2 × 3
2 × 5 =
90
composite factor = 2
2 × 5
2 =
100
composite factor = 2
2 × 3
3 =
108
composite factor = 3 × 37 =
111
composite factor = 3
3 × 5 =
135
composite factor = 2
2 × 37 =
148
composite factor = 2 × 3 × 5
2 =
150
composite factor = 2
2 × 3
2 × 5 =
180
composite factor = 5 × 37 =
185
composite factor = 2 × 3 × 37 =
222
composite factor = 3
2 × 5
2 =
225
composite factor = 2 × 3
3 × 5 =
270
composite factor = 2
2 × 3 × 5
2 =
300
This list continues below...
... This list continues from above
composite factor = 3
2 × 37 =
333
composite factor = 2 × 5 × 37 =
370
composite factor = 2
2 × 3 × 37 =
444
composite factor = 2 × 3
2 × 5
2 =
450
composite factor = 2
2 × 3
3 × 5 =
540
composite factor = 3 × 5 × 37 =
555
composite factor = 2 × 3
2 × 37 =
666
composite factor = 3
3 × 5
2 =
675
composite factor = 2
2 × 5 × 37 =
740
composite factor = 2
2 × 3
2 × 5
2 =
900
composite factor = 5
2 × 37 =
925
composite factor = 3
3 × 37 =
999
composite factor = 2 × 3 × 5 × 37 =
1,110
composite factor = 2
2 × 3
2 × 37 =
1,332
composite factor = 2 × 3
3 × 5
2 =
1,350
composite factor = 3
2 × 5 × 37 =
1,665
composite factor = 2 × 5
2 × 37 =
1,850
composite factor = 2 × 3
3 × 37 =
1,998
composite factor = 2
2 × 3 × 5 × 37 =
2,220
composite factor = 2
2 × 3
3 × 5
2 =
2,700
composite factor = 3 × 5
2 × 37 =
2,775
composite factor = 2 × 3
2 × 5 × 37 =
3,330
composite factor = 2
2 × 5
2 × 37 =
3,700
composite factor = 2
2 × 3
3 × 37 =
3,996
composite factor = 3
3 × 5 × 37 =
4,995
composite factor = 2 × 3 × 5
2 × 37 =
5,550
composite factor = 2
2 × 3
2 × 5 × 37 =
6,660
composite factor = 3
2 × 5
2 × 37 =
8,325
composite factor = 2 × 3
3 × 5 × 37 =
9,990
composite factor = 2
2 × 3 × 5
2 × 37 =
11,100
composite factor = 2 × 3
2 × 5
2 × 37 =
16,650
composite factor = 2
2 × 3
3 × 5 × 37 =
19,980
composite factor = 3
3 × 5
2 × 37 =
24,975
composite factor = 2
2 × 3
2 × 5
2 × 37 =
33,300
composite factor = 2 × 3
3 × 5
2 × 37 =
49,950
composite factor = 2
2 × 3
3 × 5
2 × 37 =
99,900
72 factors (divisors)
What times what is 99,900?
What number multiplied by what number equals 99,900?
All the combinations of any two natural numbers whose product equals 99,900.
1 × 99,900 = 99,900
2 × 49,950 = 99,900
3 × 33,300 = 99,900
4 × 24,975 = 99,900
5 × 19,980 = 99,900
6 × 16,650 = 99,900
9 × 11,100 = 99,900
10 × 9,990 = 99,900
12 × 8,325 = 99,900
15 × 6,660 = 99,900
18 × 5,550 = 99,900
20 × 4,995 = 99,900
25 × 3,996 = 99,900
27 × 3,700 = 99,900
30 × 3,330 = 99,900
36 × 2,775 = 99,900
37 × 2,700 = 99,900
45 × 2,220 = 99,900
50 × 1,998 = 99,900
54 × 1,850 = 99,900
60 × 1,665 = 99,900
74 × 1,350 = 99,900
75 × 1,332 = 99,900
90 × 1,110 = 99,900
100 × 999 = 99,900
108 × 925 = 99,900
111 × 900 = 99,900
135 × 740 = 99,900
148 × 675 = 99,900
150 × 666 = 99,900
180 × 555 = 99,900
185 × 540 = 99,900
222 × 450 = 99,900
225 × 444 = 99,900
270 × 370 = 99,900
300 × 333 = 99,900
36 unique multiplications The final answer:
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