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Hi,
I am a novice and I need help in converting the below to a PDF:
"

ROKA SANDERS

PARTIAL WORK

\ex{900.}{3} Mutassuk meg, hogy $\frac1{51} + \frac1{52} + \frac1{53} +
... + \frac1{200} > 1$.

\ex{901.}{3} Mutassuk meg, hogy $1 + \frac12 + \frac13 + \frac14 + ... +
\frac1{64} > 4$.

\ex{902 ...