Aptitude - Problems on H.C.F and L.C.M - Discussion
Discussion Forum : Problems on H.C.F and L.C.M - General Questions (Q.No. 30)
30.
If the sum of two numbers is 55 and the H.C.F. and L.C.M. of these numbers are 5 and 120 respectively, then the sum of the reciprocals of the numbers is equal to:
Answer: Option
Explanation:
Let the numbers be a and b.
Then, a + b = 55 and ab = 5 x 120 = 600.
 The required sum = |
1 | + | 1 | = | a + b | = | 55 | = | 11 |
| a | b | ab | 600 | 120 |
Discussion:
37 comments Page 1 of 4.
M.v.krishna said:
1 decade ago
Its not clear for me, why the product of hcf and lcm are taken as ab.
Gurinder said:
1 decade ago
@^^ Product of two numbers = Product of their H.C.F. and L.C.M.
Sonu kumar said:
1 decade ago
How product of two number will be its product of LCM and HCF?
Amol said:
1 decade ago
Why 1/a + 1/b ?
Shiva said:
1 decade ago
How product of two number will be its product of LCM and HCF?
Santosh Shegokar said:
1 decade ago
This is standard formula.
Product of any two numbers = product of their LCM and HCF
We have been asked to find the sum of reciprocals of the said numbers.
Here let number be a and b
Hence as per above formula a*b = HCF *LCM = 5 *120 =600
And also given a+b = 55.
Now reciprocals of above number will be 1/a and 1/b
Hence (1/a)+(1/b)= (a+b)/a*b= 55/600 = 11/120 (answer)
Product of any two numbers = product of their LCM and HCF
We have been asked to find the sum of reciprocals of the said numbers.
Here let number be a and b
Hence as per above formula a*b = HCF *LCM = 5 *120 =600
And also given a+b = 55.
Now reciprocals of above number will be 1/a and 1/b
Hence (1/a)+(1/b)= (a+b)/a*b= 55/600 = 11/120 (answer)
Arjunn said:
1 decade ago
What is the hcf and lcm of 150, 210, 375?
Is the product of hcf and lcm equal to product of these 3 numbers?
Is the product of hcf and lcm equal to product of these 3 numbers?
Raj said:
1 decade ago
How to find those two numbers?
Kishan said:
1 decade ago
If HCF of two numbers is 98 and LCM of numbers is 2352 then what is the sum of these numbers?
Babita loky said:
1 decade ago
The hcf and lcm of two numbers are 4 and 48 respectively. One of the number is 12. Find the other number?
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