UKMT Grey Kangaroo, 2019

Algebra Difficulty 1.0 Junior Find the answer United Kingdom

The expression $2 - 0 - 1 - 9$ contains four digits and three minus signs. What is the largest value that can be obtained by inserting exactly one pair of brackets into the expression?

(A) $13$ (B) $12$ (C) $10$ (D) $9$ (E) $8$

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