The product of two numbers is 2028 and their H.C.F. is 13. The number ...
Let the numbers 13a and 13b.
Then, 13a x 13b = 2028
⇒ ab = 12.
Now, the co-primes with product 12 are (1, 12) and (3, 4).
[Note: Two integers a and b are said to be coprime or relatively prime if they have no common positive factor other than 1 or, equivalently, if their greatest common divisor is 1 ]
So, the required numbers are (13 x 1, 13 x 12) and (13 x 3, 13 x 4).
Clearly, there are 2 such pairs.
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The product of two numbers is 2028 and their H.C.F. is 13. The number ...
Product of two number = LCM × HCF.
This formula is applied only for two pairs of number.So answer is 2.
The product of two numbers is 2028 and their H.C.F. is 13. The number ...
To find the number of pairs of numbers whose product is 2028 and whose highest common factor (H.C.F.) is 13, we can use the prime factorization method.
1. Prime Factorization of 2028:
To find the prime factorization of 2028, we divide it by its smallest prime factor repeatedly until we get 1.
2028 ÷ 2 = 1014
1014 ÷ 2 = 507
507 ÷ 3 = 169
169 ÷ 13 = 13
13 ÷ 13 = 1
Therefore, the prime factorization of 2028 is 2^2 × 3 × 13^2.
2. Finding the Factors:
To find the factors of 2028, we consider all the possible combinations of the prime factors obtained in the prime factorization.
The factors of 2028 are: 1, 2, 3, 4, 6, 12, 13, 26, 39, 52, 78, 169, 338, 507, 676, 1014, 2028.
3. Pairs of Numbers:
Now, we need to find the pairs of numbers whose product is 2028 and whose H.C.F. is 13.
The pairs of numbers are formed by taking one factor from the list above and dividing it by 13, and then multiplying it by another factor from the list above.
For example, let's consider the factor 13:
13 ÷ 13 = 1
Now, we need to find the other factor that, when multiplied by 1, gives the product 2028.
2028 ÷ 1 = 2028
Therefore, one pair of numbers is (1, 2028).
Similarly, we can find another pair of numbers:
26 ÷ 13 = 2
2028 ÷ 2 = 1014
Therefore, the other pair of numbers is (2, 1014).
Hence, there are two pairs of numbers whose product is 2028 and whose H.C.F. is 13. Therefore, the correct answer is option 'B' (2).