GMAT Data Sufficiency (DS) | Re: In the diagram above each of the letters represents one of the digits

the question states: between 5 and 9, not inclusive.. so we are left with numbers 6,7,8.

(1) k + l = 14
k= 8, l=6 or k=6, l=8 in either case we are left with m=7 .. so it is sufficient

2) w + z = 15
a) w= 8, z= 7
m can be 6 or 8

b) w= 7, z= 8
m can be 6 or 7

clearly insufficient

Answer is A

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