‘Ses fameuses fables, qui paraissent toute simples..’

Hi Joy, 

This the Kwiziq lesson with the answer to your question -

https://progress.lawlessfrench.com/revision/grammar/tout-tous-and-toute-toutes-all-all-of-them-the-whole-indefinite-pronouns

 

Look at the specific case when 

Tout/toute (adverb ) +adjectif = very /completely + adjective 

Hope this helps!