Is it true that l ≠ m ? (1) lm = 10 (2) mn = 10

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Is it true that l ≠ m ?

(1) lm = 10

(2) mn = 10

riteshdollar · Answer

(1) Im = 10,
I maybe equal to m if both I = m = √10
I may not be equal to m if either of I or m is equal to 10 and another 1.
Not Sufficient.

(2)mn = 10
Doesn't give any relationship between I and m.
Not Sufficient.

Together (1) and (2),
Statement (2) doesn't add value to the statement (1).
Not Sufficient.

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riteshdollar · Answer

(1) Im = 10,
I maybe equal to m if both I = m = √10
I may not be equal to m if either of I or m is equal to 10 and another 1.
Not Sufficient.

(2)mn = 10
Doesn't give any relationship between I and m.
Not Sufficient.

Together (1) and (2),
Statement (2) doesn't add value to the statement (1).
Not Sufficient.

Posted from my mobile device

unraveled · Answer

Is it true that l ≠ m ?

(1) lm = 10
Case I: 2*5 = 10 l = 2, m = 5 YES
Case II:  \sqrt{10}*\sqrt{10} = 10   l = \sqrt{10}, m = \sqrt{10}  NO

INSUFFICIENT.

(2) mn = 10
Nothing about l given.

INSUFFICIENT.

Together 1 and 2
lm - mn = 10 - 10
m(l - n) = 0 
Neither of the three can be '0'. So, 
Case I: m = 2, l = n = 5 YES
Case II: m = l = n =  \sqrt{10}  NO

Answer E.

freedom128 · Answer

Q. l ≠ m ?

(1) lm = 10
If l=m=√10, then lm=10 and l=m
If l=1 and m=10, then lm=10 but l≠m
NOT SUFFICIENT

(2) mn = 10
No available information on l
NOT SUFFICIENT

COMBINED
If l=m=n=√10, then lm=10, mn=10, and l=m
If l=n=1 and m=10, then lm=10, mn=10, but l≠m
NOT SUFFICIENT

FINAL ANSWER IS (E)

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madgmat2019 · Answer

(1) lm = 10............l,m can be srt(10) each or 10,1 ; 5,2 ..........INSUFFICIENT

(2) mn = 10...........m,n can be srt(10) each or 10,1 ; 5,2 ..........INSUFFICIENT

combining both, no extra info.....they can be both as above

OA:E

exc4libur · Answer

(1) insuf
lm=10, l=sqrt10 and m=sqrt10, l=m
lm=10, l=1, m=10, l != m

(2) insuf

(1/2) insufic
lm=mn, {l,m,n}=sqrt10, l=m
lm=mn, {l,n}=1, m=10, l != m

ans (E)

minustark · Answer

Is it true that l ≠ m ?

(1) lm = 10

(2) mn = 10

1) when l = m =  \sqrt{10} , the answer is no. when one of l and m is 2 and another is 5. answer is yes. not sufficient
2) just like 1, m and n can assume a varieties of values. not sufficient.
Combined, l = m =n =  \sqrt{10} . l = m.
again, l = 2, m =5, n =2. l is not equal to m. 
E is the answer.

monikakumar · Answer

Is it true that l ≠ m ?

(1) lm = 10

(2) mn = 10
1) l=10^1/2, m=10^1/2
l=1, m=10
insufficient
2)value of l is unknown
1+2)
insufficient
Ans E

NiftyNiffler · Answer

Is it true that l ≠ m ?

(1) lm = 10

(2) mn = 10

Nothing is mentioned about the number types of l,m or n. They could all very well be \sqrt{10}. So  E

Is it true that l ≠ m ? (1) lm = 10 (2) mn = 10

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