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HCF and LCM of two numbers are 7 and 140 respectively. If the numbers are between 20 and 45, the sum of the numbers is :
- A70
- B77
- C63
- D56
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0
CCommunity
63 is the right answer
0
CCommunity
Let the numbers be 7x and
7y where x and y are co-prime.
Now, LCM of 7x and 7y = 7xy
7xy = 140
xy =$\frac{140}{7}$ =20
Now, required values of x and y
whose product is 50 and are coprime,
will be 4 and 5.
Numbers are 28 and 35 which
lie between 20 and 45.
Required sum = 28 + 35 = 63
7y where x and y are co-prime.
Now, LCM of 7x and 7y = 7xy
7xy = 140
xy =$\frac{140}{7}$ =20
Now, required values of x and y
whose product is 50 and are coprime,
will be 4 and 5.
Numbers are 28 and 35 which
lie between 20 and 45.
Required sum = 28 + 35 = 63