the official guides are definitely the best way to go.
for "fundamentals", though, you may also want to consider our MGMAT strategy guides. (they're interestingly named - "strategy guides" even though their content could be more aptly described as content than as strategy.)
those guides will help you learn - or re-learn, as the case may be - the fundamentals behind the official problems.
there are 8 of them, each for its own separate topic (5 different math topics - geometry, word translations, number properties, fractions/decimals/percents, and algebra/equations/inequalities - and 3 different verbal topics - SC, CR, and RC).
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Quand on se sent bien dans un vêtement, tout peut arriver. Un bon vêtement, c'est un passeport pour le bonheur.
Yves Saint-Laurent
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