Answer:
"How d-u-m-b can you get!" said Robert. "A co-l-o-s-s-a-l waste of time if you ask me. So get going! S-c-r-a-m! S-h-o-o!"
Explanation:
"The Number Devil: A Mathematical Adventure" is a book written by Hans Ma-g-n-us En-zen-s-ber-ger. The book is about a young boy named Robert, who does not like Mathematics, eventually meet a number devil, named Te-plot-a-xl. Te-plot-a-xl then teaches Robert maths over the period of twelve dreams.
The excerpt from the book which suggests that the sole purpose of Robert was to oppose the number devil is,
"How d-u-m-b can you get!" said Robert. "A co-l-o-s-s-a-l waste of time if you ask me. So get going! S-c-r-a-m! S-h-o-o!"
In this excerpt, he is seen chasing away the number devil.
