Data Sufficiency (DS) | Re: Each person attending a fund-raising party for a certain club was

admission fee = a
person attended = p
total amount = t
t = a*p (as each person will pay some amount)

1) => (a+0.75) (p+100) = t => Insufficient, three variable two equation
2) => (a-1.5) (p - 100) = t => Insufficient, three variable two equation

1+2 => sufficient, three variable three equation

Ans => C

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