I think it's D. To sum the fractions, we need a common denominator. First, we need to know the least common multiple of 36 and 64.
Factor the 2 numbers into their prime factors:
36 = 2*2*3*3 = (2^2)*(3^2)
64 = 2*2*2*2*2*2 = (2^6)
The LCM can be found by multiplying together the highest power of each prime factor that occurs in the 2 numbers. Therefore,
LCM(36,64) = (2^6)*(3^2) = 576.
This will be our common denominator to sum the fractions, so
(1/36) + (1/64) becomes (16/576) + (9/576) = (25/576).
Then sqrt(25/576) = 5/24.
square root question
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mschling52
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samirpandeyit62
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The ans should be D
we have sqrt (1/36 +1/64)= ?
cross multiply 1/36 +1/64
= sqrt (36+64/36X64)
=sqrt(100/36X64)
=sqrt (100)/sqrt(36)Xsqrt(64)
= 10/6.8
=5/24
we have sqrt (1/36 +1/64)= ?
cross multiply 1/36 +1/64
= sqrt (36+64/36X64)
=sqrt(100/36X64)
=sqrt (100)/sqrt(36)Xsqrt(64)
= 10/6.8
=5/24
Regards
Samir
Samir
